Hukum Hess adalah sebuah hukum dalam kimia fisik untuk ekspansi Hess dalam siklus Hess. Hukum ini digunakan untuk memprediksi perubahan entalpi dari hukum kekekalan energi (dinyatakan sebagai fungsi keadaan ΔH).

Menurut hukum Hess, karena entalpi adalah fungsi keadaan, perubahan entalpi dari suatu reaksi kimia adalah sama, walaupun langkah-langkah yang digunakan untuk memperoleh produk berbeda. Dengan kata lain, hanya keadaan awal dan akhir yang berpengaruh terhadap perubahan entalpi, bukan langkah-langkah yang dilakukan untuk mencapainya.
Hal ini menyebabkan perubahan entalpi suatu reaksi dapat dihitung sekalipun tidak dapat diukur secara langsung. Caranya adalah dengan melakukan operasi aritmatika pada beberapa persamaan reaksi yang perubahan entalpinya diketahui. Persamaan-persamaan reaksi tersebut diatur sedemikian rupa sehingga penjumlahan semua persamaan akan menghasilkan reaksi yang kita inginkan. Jika suatu persamaan reaksi dikalikan (atau dibagi) dengan suatu angka, perubahan entalpinya juga harus dikali (dibagi). Jika persamaan itu dibalik, maka tanda perubahan entalpi harus dibalik pula (yaitu menjadi -ΔH).
Selain itu, dengan menggunakan hukum Hess, nilai ΔH juga dapat diketahui dengan pengurangan entalpi pembentukan produk-produk dikurangi entalpi pembentukan reaktan. Secara matematis

Larutan buffer adalah larutan yang terdiri dari garam dengan asam lemahnya atau garam dengan basa lemahnya. Komposisi ini menyebabkan larutan memiliki kemampuan untuk mempertahankan pH jika kedalam larutan ditambahkan sedikit asam atau basa. Hal ini disebabkan larutan penyangga memiliki pasangan asam basa konyugasi (ingat konsep asam Lowry-Bronsted) perhatikan Bagan 8.24.

Bagan 8.24. Skema larutan buffer dan komposisi asam basa konyugasi
Kita ambil contoh pasangan antara asam lemah CH3COOH dengan garamnya CH3COONa. Di dalam larutan
CH3COONa ⇄ CH3COO- + Na+ (Garam)
CH3COOH ⇄ CH3COO- + H+ (Asam lemah)
Dalam larutan terdapat CH3COOH merupakan asam dan CH3COO- basa konyugasi.
Kehadiran senyawa dan ion ini yang dapat menetralisir adanya asam dan basa dalam larutan. Jika larutan ini ditambahkan asam, terjadi reaksi netralisasi,
H+ + CH3COO- ⇄ CH3COOH
Kehadiran basa dinetralisir oleh CH3COOH
OH- + CH3COOH ⇄ CH3COO- + H2O
Untuk larutan buffer dengan komposisi lain adalah campuran antara garam dengan basa lemahnya, seperti campuran NH4Cl dengan NH4OH. Garam terionoisasi
NH4Cl ⇄ NH4+ + Cl-
NH4OH ⇄ NH4+ + OH-

Dalam larutan garam terdapat pasangan basa dan asam konyugasi dari NH4OH dan NH4+, adanya molekul dan ion ini menyebabkan larutan mampu mempertahankan pH larutan. Tambahan H+ dapat dinetralisir oleh NH4OH sesuai dengan reaksi :
NH4OH + H+ ⇄ NH4+ + H2O
Demikian pula adanya tambahan basa OH- dinetralisir oleh ion amonium dengan reaksi :
NH4+ + OH- ⇄ NH4OH
Larutan buffer yang terdiri dari garam dan asam lemahnya atau basa lemahnya memiliki harga pH yang berbeda dari garamnya ataupun dari asam lemahnya, karena kedua larutan terionisasi.

Parts of Speech Table

This is a summary of the 8 parts of speech*. You can find more detail if you click on each part of speech.

part of speech	function or "job"	example words	example sentences
Verb	action or state	(to) be, have, do, like, work, sing, can, must	EnglishClub.com is a web site. I like EnglishClub.com.
Noun	thing or person	pen, dog, work, music, town, London, teacher, John	This is my dog. He lives in my house. We live in London.
Adjective	describes a noun	a/an, the, 2, some, good, big, red, well, interesting	I have two dogs. My dogs are big. I like big dogs.
Adverb	describes a verb, adjective or adverb	quickly, silently, well, badly, very, really	My dog eats quickly. When he is very hungry, he eats really quickly.
Pronoun	replaces a noun	I, you, he, she, some	Tara is Indian. She is beautiful.
Preposition	links a noun to another word	to, at, after, on, but	We went to school on Monday.
Conjunction	joins clauses or sentences or words	and, but, when	I like dogs and I like cats. I like cats and dogs. I like dogs but I don't like cats.
Interjection	short exclamation, sometimes inserted into a sentence	oh!, ouch!, hi!, well	Ouch! That hurts! Hi! How are you? Well, I don't know.

* Some grammar sources categorize English into 9 or 10 parts of speech. At EnglishClub.com, we use the traditional categorization of 8 parts of speech. Examples of other categorizations are:

• Verbs may be treated as two different parts of speech:
  • Lexical Verbs (work, like, run)
  • Auxiliary Verbs (be, have, must)
• Determiners may be treated as a separate part of speech, instead of being categorized under Adjectives

Parts of Speech Examples

Here are some sentences made with different English parts of speech:

verb Stop!

noun verb John works.

noun verb verb John is working.

 

pronoun verb noun She loves animals.

noun verb adjective noun Animals like kind people.

 

noun verb noun adverb Tara speaks English well.

noun verb adjective noun Tara speaks good English.

 

pronoun	verb	preposition	adjective	noun	adverb
She	ran	to	the	station	quickly.

 

pron.	verb	adj.	noun	conjunction	pron.	verb	pron.
She	likes	big	snakes	but	I	hate	them.

Here is a sentence that contains every part of speech:

interjection	pron.	conj.	adj.	noun	verb	prep.	noun	adverb
Well,	she	and	young	John	walk	to	school	slowly.

Words with More than One Job

Many words in English can have more than one job, or be more than one part of speech. For example, "work" can be a verb and a noun; "but" can be a conjunction and a preposition; "well" can be an adjective, an adverb and an interjection. In addition, many nouns can act as adjectives.
To analyze the part of speech, ask yourself: "What job is this word doing in this sentence?"
In the table below you can see a few examples. Of course, there are more, even for some of the words in the table. In fact, if you look in a good dictionary you will see that the word "but" has six jobs to do:

• verb, noun, adverb, pronoun, preposition and conjuction!

word	part of speech	example
work	noun	My work is easy.
	verb	I work in London.
but	conjunction	John came but Mary didn't come.
	preposition	Everyone came but Mary.
well	adjective	Are you well?
	adverb	She speaks well.
	interjection	Well! That's expensive!
afternoon	noun	We ate in the afternoon.
	noun acting as adjective	We had afternoon tea.

Kaidah Pencacahan

---

1. Aturan Perkalian

Misalkan, dari 3 orang siswa, yaitu Algi, Bianda, dan Cahyadi akan dipilih untuk menjadi ketua kelas, sekretaris, dan bendahara dengan aturan bahwa seseorang tidak boleh merangkap jabatan pengurus kelas. Banyak cara 3 orang dipilih menjadi pengurus kelas tersebut akan dipelajari melalui uraian berikut.

Amati Gambar di atas!
a. Untuk ketua kelas (K)
Posisi ketua kelas dapat dipilih dari 3 orang, yaitu Algi (A), Bianda (B), atau Cahyadi (C).
Jadi, posisi ketua kelas dapat dipilih dengan 3 cara.
b. Untuk Sekretaris (S)
Jika posisi ketua kelas sudah terisi oleh seseorang maka posisi sekretaris hanya dapat dipilih dari 2 orang yang belum terpilih menjadi pengurus kelas.
Jadi, posisi sekretaris dapat dipilih dengan 2 cara.
c. Untuk Bendahara (H)
Jika posisi ketua kelas dan sekretaris sudah terisi maka posisi bendahara hanya ada satu pilihan, yaitu dijabat oleh orang yang belum terpilih menjadi pengurus kelas.
Jadi, posisi bendahara dapat dipilih dengan 1 cara.
Dengan demikian, banyak cara yang dilakukan untuk memilih 3 orang pengurus kelas dari 3 orang kandidat adalah
3 × 2 × 1 = 6 cara.

Uraian tersebut akan lebih jelas apabila mengamati skema berikut.

Misalkan,
• operasi 1 dapat dilaksanakan dalam n1 cara;
• operasi 2 dapat dilaksanakan dalam n2 cara;
• operasi k dapat dilaksanakan dalam nk cara.
Banyak cara k operasi dapat dilaksanakan secara berurutan adalah
n = n1 × n2 × n3 ... × nk.



Contoh:
Berapa cara yang dapat diperoleh untuk memilih posisi seorang tekong, apit kiri, dan apit kanan dari 15 atlet sepak takraw pelatnas SEA GAMES jika tidak ada posisi yang rangkap? (Tekong adalah pemain sepak takraw yang melakukan sepak permulaan).
Jawab:
• Untuk posisi tekong.
Posisi tekong dapat dipilih dengan 15 cara dari 15 atlet pelatnas yang tersedia.
• Untuk posisi apit kiri.
Dapat dipilih dengan 14 cara dari 14 atlet yang ada (1 atlet lagi tidak terpilih karena menjadi tekong).
• Untuk posisi apit kanan.
Cara untuk memilih apit kanan hanya dengan 13 cara dari 13 atlet yang ada ( 2 atlet tidak dapat dipilih karena telah menjadi tekong dan apit kiri).
Dengan demikian, banyak cara yang dilakukan untuk memilih posisi dalam regu sepak takraw adalah 15 × 14 × 13 = 2.730 cara.

2. Faktorial
Anda telah mempelajari, banyak cara yang dilakukan untuk memilih 3 orang pengurus kelas dari 3 orang kandidat adalah 3 × 2 × 1 = 6 cara.
Selanjutnya, 3 × 2 × 1 dapat dinyatakan dengan 3! (dibaca 3 faktorial). Jadi,

Dengan penalaran yang sama
4! = 4 × 3 × 2 × 1 = 4 × 3! = 4 × 6 = 24
5! = 5 × 4 × 3 × 2 × 1 = 5 × 4! = 5 × 24 = 120
6! = 6 × 5! = 6 × 120 = 720

STATISTIKA

Statistika adalah ilmu yang mempelajari cara-cara mengumpulkan data ,menyusun data,menyajikan data,menganalisis dan menarik kesimpulan.
Statistik berkaitan dengan data

1.Ada dua jenis data:
a.Data yang di peroleh dari hasil pengamatan
ex:Golongan darah A,O,AB,B
b.Data yang di peroleh dari pengukuran
ex:berat badan 25 kg,30 kg,45 kg

2.Data di susun menjadi:
a,Data tunggal
ex:7,8,5,6,7,8
b.Data kelompok
ex:0-5
     6-10 dst

3.Penyajian data:
Diagram batang
Diagram garis
Diangram lingkaran
Piktogram(dengan lambang)

4.Cara mengumpulkan data:
a.Observasi(Pengamatan) adalah tehnik pengumpulan data ,dalam hal ini pencari data mengadakan pengamatan baik langsung maupun tak langsung terhadap objek.
b.Wawancara adalah tanya jawab secara langsung dengan sumber data atau orang-orang yang di anggap mampu memberikan data yang di perlukan.
c.Angket(Kuesioner) adalah tehnik pengumpulan data dengan memberikan pertanyaan-pertanyaan yang di susun dalam suatu daftar pertanyaan.

5.Populasi dan Sampel
a.Populasi adalah kumpulan semua objek yang di bicarakan.
ex:Siswa kelas IX SMP N 10 Jakarta Barat
b.Sampel adalah beberapa objek yang di ambil dari populasi.
ex:Siswa kelas IX SMP N10 yang memakai kacamata

6.Ukuran Tedensi Sentral(Ukuran Pemusatan)
a.Mean
adalah jumlah semua datum di bagi dengan banyaknya datum.

 Mean=Jumlah semua datum / banyaknya datum

b.Median
adalah suatu nilai yang membagi suatu data yang telah di urutkan menjadi dua bagian sama banyak.
 c.Modus
adalah nilai datum yang sering muncul atau nilai datum yang frekuensinya (kekerapan atau keseringan muncul)paling besar.

7.Ukuran Penyebaran
   1.Kuartil
adalah tiga nilai yang membagi data yang sudah di urutkan menjadi empat bagian yang sama banyak. Kuartil ada tiga:
a.Median atau kuartil kedua (Q2) yaitu nilai yang membagi data yang sudah di urutkan menjadi dua bagian yang sama banyak.
b.Kuartil pertama atau kuartil bawah (Q1) yaitu median dari semua datavyang nilainya kurang dari kuartil ke dua
c.Kuartil ke tiga atau kuartil atas(Q3) yaitu median dari semua data yang nilai lebih dari kuarti ke dua.
    2.Jangkaun data dan jangkauan antar kuartil
a.Jangkaun data(J)
di denifisikan sebagai selisih antara nilai statistik maksimum dan statistik minimum .

J=statistik maksimum-statistik minimum=Xmaks-Xmin

 b.Jangkauan Antarkuartil
adalah selisih antara nilai kuartol atas dan kuartil bawah .

JK=Q3-Q1

 c.Jangkauan semiinterkuartil
Jangkauan semiinterkuartil atau simpangan kuartil (Qd)adalah setengah dari jangkauan  antarkuartil.

Qd=1/2 (Q3-Q1)

Pronouns

Definition: A pronoun usually refers to something already mentioned in a sentence or piece of text. A pronoun is a word that substitutes a noun or noun phrase used to prevent repetition of the noun to which they refer. One of the most common pronouns is it.

Rule for Pronouns A pronoun must agree with the noun it refer. Therefore, if the noun is singular, therefore the pronoun must be singular; if the noun is plural, use a plural pronoun; if the noun is feminine, use a feminine pronoun, and so on. For example: The train was late, it had been delayed. The trains were late, they had been delayed. Types of pronouns English Pronouns are divided into sub-categories. These are Demonstrative, Personal, Reflexive, Possessive, Interrogative, Negative, Reciprocal, Relative and Quantifier Type About Example Personal Pronoun Takes the place of a specific or named person or thing. I, you, he, she, etc.. Reflexive Pronoun Adds information by pointing back to a noun or another pronoun. myself, yourself, etc.. Demonstrative Pronoun Points out a specific person, place, or thing. this, that, these, those Relative pronoun Begins a subordinate clause and relates the clause to a word in the main clause. who, whose, which, that, etc.. Interrogative Pronoun Is used to ask a question. who, what, where, etc.. Possessive Pronoun Used to substitute a noun and to show possession or ownership. mine, yours, his, etc.. Negative Pronoun nothing, no, nobody, etc.. Reciprocal pronoun Express an interchangeable or mutual action or relationship. each other, one another Quantifier some, any, something, much, etc.

Personal Pronoun

Definition: Personal pronouns refer to the person who is doing the action or to whom the action affects. In that way we distinguish two types of personal pronouns: Personal "Subject Pronouns" and Personal "Object Pronouns".

Personal Pronouns Subject form Object form I Me You You He him she her it it we us you you they them Personal Subject Pronouns We use the Personal Subject Pronouns to refer to the person who is doing the action of the verb or the verb speaks about. A subjective personal pronoun indicates that the pronoun is acting as the subject of the sentence. For example: Jhon is listening to music. => He listens to music every day. * In this case, "he" substitutes "Jhon" which is the subject of the sentence. Are you the delegates from Malagawatch? After many years, they returned to their homeland. Personal Object Pronouns We use the Personal Object Pronouns to refer to the person whom the action of the verbs affects. An objective personal pronoun indicates that the pronoun is acting as an object of a verb, compound verb, preposition, or infinitive phrase. For example: Seamus stole the selkie's skin and forced her to live with him. * The objective personal pronoun "her" is the direct object of the verb "forced" and the objective personal pronoun "him" is the object of the preposition "with." Deborah and Roberta will meet us at the newest café in the market. * Here the objective personal pronoun "us" is the direct object of the compound verb "will meet." Christopher was surprised to see her at the drag races. * Here the objective personal pronoun "her" is the object of the infinitive phrase "to see." A personal pronoun refers to a specific person or thing and changes its form to indicate person, number, gender, and case.

Reflexive Pronoun

Definition: We use the reflexive pronouns to indicate that the person who realizes the action of the verb is the same person who receives the action. Reflexive pronouns are identical in form to intensive pronouns.

Subject Reflexive Singular I You He She It myself yourself himself herself itself Plural We You They ourselves yourselves themselves For example: I cut my hair myself. * In this example "I" does the action of cutting the hair and at the same time "I" gets the action of the hair being cut. We defended ourselves brilliantly. * In this example the reflexive pronoun "ourselves" refers back to the subject of the sentence. John talks to himself when he is nervous. * In this example "Himself" refers to John. Reflexive pronouns always act as objects not subjects, and they require an interaction between the subject and an object. For example: Because she was not hungry when the cake was served, Ellen saved herself a piece. * In the independent clause, "Ellen" is the subject and "herself" is a reflexive pronoun acting as the indirect object. This sentence is grammatically correct. Jhon and myself are going to the movie. * In this sentence, "Jhon" and "myself" are the subjects. Reflexive pronouns cannot be subjects. This sentence is grammatically incorrect. Care must be taken to identify whether the noun is singular or plural and choose the pronoun accordingly. For example: Nor is she shy about giving herself credit for it. We gave ourselves a second chance to complete the course. Did they lock themselves out of the house again? Give yourselves a pat on the back for a job well done. Note: The reflexive pronoun can also be used to give more emphasis to the subject or object (intensive pronoun). For example: I did it myself. * I want to emphasise the fact that I did it. Examples: He washed himself. She looked at herself in the mirror. Diabetics give themselves insulin shots several times a day. After the party, I asked myself why I had faxed invitations to everyone in my office building. Richard usually remembered to send a copy of his e-mail to himself.

Demonstrative pronoun

Definition: Demonstrative pronouns are pronouns that point to specific things. "This, that, these, those, none and neither" are Demonstrative Pronouns that substitute nouns when the nouns they replace can be understood from the context. At the same time, to indicate whether they are close or far, in space or time, from the speaker in the moment of speaking. They also indicate whether they are replacing singular or plural words. Some grammars describe them as members of the class of function words called "determiners", since they identify nouns and other nominals. "This" (singular) and "These" (plural) refer to an object or person NEAR the speaker. "That" (singular) and "Those" (plural) refer to an object or person further AWAY. For example: This is unbelievable. * In this example, "this" can refer to an object or situation close in space or in time to the speaker. That is unbelievable. * In this example, "that" can refer to an object or situation farther in space or in time to the speaker. These are unbelievable. * In this example, "these" can refer to some objects close in space or in time to the speaker. Those are unbelievable. * In this example, "those" can refer to some objects farther in space or in time to the speaker. Position Before the noun. Before the word 'one'. Before an adjective + noun. Alone when the noun is 'understood' Examples Who owns that house? (distant - physical ) Is this John's house? (near - physical ) That's nothing to do with me.. (distant - psychological ) This is a nice surprise! (near - psychological )

this, that, these and those

Why do we use this and these?

We use this (singular) and these (plural) as pronouns:
- to talk about people or things near us:

This is a nice cup of tea.
Whose shoes are these?

- to introduce people:

This is Janet.
These are my friends, John and Michael.

WARNING:
We don’t say These are John and Michael.
We say This is John and this is Michael.

- to introduce ourselves to begin a conversation on the phone:

Hello, this is David, Can I speak to Sally?

Why do we use that and those?

We use that (singular) and those (plural):
- to talk about things that are not near us:

What’s that?
This is our house, and that’s Rebecca’s house over there.
Those are very expensive shoes.

- We also use that to refer back to something someone said or did:

• - Shall we go to the cinema?
  - Yes, that’s a good idea.
• - I’ve got a new job.
  - That’s great.
• - I’m very tired.
  - Why is that?

this, these, that, those with nouns

We also use this, these, that and those with nouns to show proximity
We use this and these for people or things near us:

We have lived in this house for twenty years.
Have you read all of these books?

… and that and those for things that are not near us:

Who lives in that house?
Who are those people?

Relative Pronoun

Definition: We use the relative pronouns to refer to a noun mentioned before and of which we are adding more information. They are used to join two or more sentences and forming in that way what we call "relative sentences". Relative pronouns Who, Whom, That, Which whoever, whomever, whichever For example: People who speak two languages are called bilingual. * In this example, the relative "who" introduces the relative sentence "speak two languages" that describes or gives more information about the noun "people". Relative pronouns: Subject or Object As the relative pronouns relate to another noun preceding it in the sentence, they connect a dependent clause to an antecedent (a noun that precedes the pronoun.) Therefore, relative pronouns acts as the subject or object of the dependent clause. For example: The chef who won the competition studied in Paris. * Here, "who" relates back to (or is relative to) the noun "Chef". "Who" also acts as the subject of the dependent clause and the verb "won". => The dependent clause: who won the competition. => The independent clause: The chef studied in Paris. The shirt that Carl bought has a stain on the pocket. * Here, "that" relates back to (or is relative to) the noun "shirt". "That" is also the object of the verb "bought". => The dependent clause is: that Carl bought. => The independent clause: The shirt has a stain on the pocket. Referring to people: Who, Whom, Whoever, Whomever These pronouns take a different case depending on whether the relative pronoun is a subject or an object in the dependent clause. Subjective case Use the subjective case when these relative pronouns are the subject (initiating the action) of the dependent clause: Who, Whoever For example: Negotiations were not going smoothly between the two leaders, who made no bones about not liking each other. * "Who" relates back to the noun "leaders" and is the subject of the dependent clause and the verb "made". Most workers, whoever was not employed by the auto manufacturer, toiled at one of the millions of little minnow companies. * "Whoever" relates back to the noun "workers" and is the subject of the dependent clause and the verb "was employed". Objective case Use the objective case when these relative pronouns are the object (receiving the action) of the dependent clause: Whom, Whomever For example: This is the approach taken by journalists, whom some consider to be objective. * "Whom" relates back to the noun "journalists" and is the object of the verb "consider". The subject of the dependent clause is "some". The three representatives, whomever the committee chooses, should be at the meeting tomorrow. * "Whomever" relates back to the noun representatives and is the object of the verb "chooses". The subject of the dependent clause is "Committee". Referring to a place, thing or idea: Which, That When using relative pronouns for places, things or ideas, rather than determining case, the writer must decide whether the information in the dependent clause is essential to the meaning of the independent clause or simply additional information. When information is critical to the understanding of the main clause, use That as the appropriate relative pronoun and do not set the information off by commas. For example: Russian generals have delivered a message that is difficult to ignore. * "That" relates back to the noun "message" and is necessary for the reader to know what "message" the sentence is about. There is another factor that obviously boosts the reputation of both of these men. * "That" relates back to the noun "factor" and is necessary for the reader to know what "factor" the sentence is about. When information is not critical to the understanding of the main clause, use "Which" as the appropriate relative pronoun and set the information off by commas. For example: The toughest intramural fight of all for Clinton was the North American Free Trade Agreement, which he undertook a full year before the 1994 election. * "Which" relates back to the noun "agreement" and the information following it is not necessary for the reader to know what "agreement" the sentence is about. Clinton refused to head toward the center on affirmative action and abortion, which are the two most sacred issues to the traditional liberal wing of the party. * "Wich" relates back to the noun "affirmative action and abortion" and the information following it is not necessary for the reader to know what "affirmative action and abortion" the sentence is about. When referring to more than one place, thing or idea use these relative pronouns: Whatever, Whichever For example: The three approaches, whichever works is fine, produce a more ambiguous picture of a man. * "Whichever" relates to the noun "approaches" and the information contained within the commas is additional, not critical information. Any excessive profits, whatever exceeded accepted limits, would attract the notice of representatives. * "Whatever" relates to the noun "profits" and the information contained within the commas is additional, not critical information.

Interrogative Pronoun

Definition: An interrogative pronoun is a pronoun used in order to ask a question. Some of them refer only to people, like "who" and others refer to people and objects, etc like "what". They do not distinguish between singular and plural, so they only have one form. Interrogative pronouns produce information questions that require more than a "yes" or "no" answer. For example: ·  What is her phone number? ·  What do you want? Interrogative pronouns are: What, Which, Who, Whose, Whom. In addition, these pronouns may take the suffixes -ever and -soever. Forms: As we can see in the next table, these pronouns could act as a subject, object or possessive in a sentence. Subject Object Possessive who whom whose which that   WHAT can be used to ask about objects or people. For example: What time is it? What is your name? What do you want? WHICH can be used to ask about objects or people. For example: Which chair are you talking about? Which jumper do you like? Which is your mother? WHO can be used to ask about people For example: Who are you? Which is your mother? Who has been sitting in my chair? WHOSE can be used to ask about a possession relation. For example: Whose is this book? Whose car did you drive here? WHOM can be used to ask about people.It is less usual and more formal than "who" For example: Whom did you phone? For whom will you vote? NOTE: Either "which" or "what" can also be used as an interrogative adjective, and that "who," "whom," or "which" can also be used as a relative pronoun. For example: The man whom she chose will do a wonderful job. Examples Who is in charge? Which wants to see the dentist first? Who wrote the novel Rockbound? Whom do you think we should invite? What did she say?

Possessive Pronoun

Definition: We use the Possessive Pronouns when we want to substitute a group of words that are indicating a possession relation. Subject Possessive I Mine You Yours He His She Hers It Its We Ours You Yours They Theirs For example: This is my book. * In this example, we can substitute "my book" for the possessive pronoun "mine". => This is mine. This is your disk and that's mine. * Mine substitutes the word disk and shows that it belongs to me. A possessive pronoun indicates it is acting as a subject complement or a subject of the sentence. For example: The smallest gift is mine. This is yours. * Here the possessive pronouns acts as a subject complement. His is on the kitchen counter. Theirs will be delivered tomorrow. Ours is the green one on the corner. * Here the possessive pronoun acts as the subject of the sentence. Note : Possessive pronouns are very similar to possessive adjectives. For example: You can borrow my book as long as you remember that it's not yours. => The possessive "my" depends on the noun "book." => The possessive "yours" is a pronoun which stands in the place of "your book". When you drive to Manitoba, will you take your car or theirs? => The possessive "your" depends on the noun "car." => The possessive pronoun, "theirs," stands in the place of the noun phrase, "their car." Reciprocal pronoun Definition: We use the reciprocal pronouns to indicate that two people can carry out an action and get the consequences of that action at the same time. There are two reciprocal pronouns: Reciprocal pronouns each other one another They enable you to simplify sentences where the same general idea is expressed two or more times. For example: On their wedding day Jhon gave Mary a gold ring and Mary gave Jhon a gold ring. * Using the reciprocal pronoun, "each other", this could be rewritten: => On their wedding day Mary and Jhon gave each other gold rings. Peter and Mary kissed each other. * In this example "each other" indicates that both people involved in the action of "kissing" got the result, kisses, at the same time. If you need to refer to more than two people, say the students in a classroom, then we could use the reciprocal pronoun, "one another". For example: The students in this classroom cooperate with one another. The teachers gathered to congratulate one another on the year's conclusion.

 

indefinite pronouns

The indefinite pronouns are:

somebody	someone	something
anybody	anyone	anything
nobody	no one	nothing
everybody	everyone	everything

We use indefinite pronouns to refer to people or things without saying exactly who or what they are. We use pronouns ending in -body or -one for people, and pronouns ending in -thing for things:

Everybody enjoyed the concert.
I opened the door but there was no one at home.
It was a very clear day. We could see everything.

We use a singular verb after an indefinite pronoun:

Everybody loves Sally.
Everything was ready for the party.

When we refer back to an indefinite pronoun we normally use a plural pronoun:

Everybody enjoyed the concert. They stood up and clapped.
I will tell somebody that dinner is ready. They have been waiting a long time.

We can add -'s to an indefinite pronoun to make a possessive.

They were staying in somebody’s house.
Is this anybody’s coat?

We use indefinite pronouns with no- as the subject in negative clauses (not pronouns with any.)

Anybody didn’t come >> Nobody came.

We do not use another negative in a clause with nobody, no one or nothing:

Nobody came.
Nothing happened.

We use else after indefinite pronouns to refer to people or things in addition to the ones we already mentioned.

All the family came, but no one else.
If Michael can’t come we’ll ask somebody else.
So that's eggs, peas and chips. Do you want anything else?

 

one and ones

We use one (singular) and ones (plural) to avoid unnecessary repetition.

See those two girls? Helen is the tall one and Jane is the short one.
Which is your car, the red one or the blue one?
My trousers are torn. I need some new ones.
See those two girls. Helen is the one on the left.
Let’s look at the photographs. The ones you took in Paris.

We often use them after Which ... in questions:

You can borrow a book. Which one do you want?
There are lots of books here. Which ones are yours?

questions

Which question word to use?

We use who to ask questions about people:

Who is that?
Who lives here?
Who did you see?

We use whose to ask about possession:

Whose coat is this? [or] Whose is this coat?
Whose book is that? [or] Whose is that book?
Whose bags are those? [or] Whose are those bags?

We use what to ask questions about things:

What is that?
What do you want?

We use which to ask someone to choose something:

Which came first, the chicken or the egg?
I’ve got two books. Which do you want?

We can also use what and which with nouns:

What subjects did you study at school?
What newspaper do you read?
Which newspaper do you read – the Times or the Guardian?
Which book do you want?
Which one is yours?

Questions with prepositions:

Questions ending in prepositions are very common in English. After Who, Which or What we often have a preposition at the end of the sentence:

Who does this book belong to?
What are you looking for?
Which university did you go to?
What country do you come from?