There are 9 parts of speech or word classes in English language:
– nouns
– pronouns
– determiners
– verbs
– prepositions
– adjectives
– adverbs
– conjunctions
– interjections

We use conjunctions to connect words, phrases or clauses.

Jack and Jill went to the cinema last night.
– and = conjunction
– The conjunction ‘and’ connects 2 words (Jack and Jill)

I met my teacher and her husband yesterday.
– and = conjunction
– phrase = a combination of 2 words or more
– The conjunction ‘and’ connects 2 phrases (my teacher and her husband)

He knocked on the door and we went in.
– and = conjunction
– clause = a group of words that consists of at least 1 subject and 1 verb
– The conjunction ‘and’ connects 2 clauses
– 1st clause: He knocked on the door (subject= he, verb = knocked)
– 2nd clause: We went in (subject= we, verb = went in)

Independent Clauses

There are 2 types of clauses:
– Independent clauses
– Dependent clauses

Independent clause is a clause that can stand on its on (can be understood on its own).

He knocked on the door and we went in.
– ‘He knocked on the door’ = independent clause
If it is not combined with ‘we went in’, we can still understand the clause.
– ‘We went in’ = independent clause
If it is not combined with ‘he knocked on the door’, we can still understand the clause.

It’s an old car, but it’s very reliable.
– ‘It’s an old car’ = independent clause
If it is not combined with ‘it’s very reliable’, we can still understand the clause.
– ‘It’s very reliable’ = independent clause
If it is not combined with ‘it’s an old car’, we can still understand the clause.

We use coordinating conjunctions to connect:
– 2 words or more that have parallel structure
– 2 phrases or more that have parallel structure
– 2 independent clauses

I like coffee, and Mary likes tea.
– and = coordinating conjunction
– ‘I like coffee’ = independent clause
– ‘Mary likes tea’ = independent clause

Coordinating Conjunctions
– and
– but
– for
– or
– so
– nor
– yet

And

We use ‘and’ to:
– connect two words, phrases or clause that are equal.
In this context, ‘and’ means ‘also’ or ‘in addition to’

John and I left early.
London is in England, and Rome is in Italy.

– connect 2 clauses where the second clause happens after the first clause. In this context, ‘and’ means ‘then’ or ‘following this.’

They drove five miles and stopped to eat.
There was a big bang and the lights went out.

– connect 2 clauses where the second clause happens because of the first clause

He went to bed early, and the next day he felt better.
I told him to go and he went.

But

We use ‘but’ to:
– introduce a word or phrase that contrasts with what was said before

Mary ran fast, but she couldn’t catch John.
I don’t know that woman, but John does.

Or

We use ‘or’ to:
– express choices or alternatives

You can have coffee or tea.
I’ll call John today or tomorrow.

Nor

We use ‘nor’ to:
– add something negative to another negative thing that has been mentioned previously

He is not going to the meeting, nor am I.
= He is not going to the meeting, and I am not going to the meeting.

She doesn’t like durian, nor does Jeff.
= She doesn’t like durian, and Jeff doesn’t like durian.

How to use ‘nor’ (1):
Negative clause + nor + am/is/are/was/were + Subject

Jane is not hungry, nor am I.
Jane is not hungry, nor is John.
Jane is not hungry, nor are they.
Jane was not late, nor was I.
Jane was not late, nor was John.
Jane was not late, nor were they.

How to use ‘nor’ (2):
Negative clause + nor + do/does/did + Subject

Jane does not like durian, nor do I.
Jane does not like durian, nor does John.
Jane does not like durian, nor do they.
Jane did not go, nor did I.
Jane did not go, nor did John.
Jane did not go, nor did they.

How to use ‘nor’ (3):
Negative clause + nor + has/have/had/modal verb + Subject

– Jane has not eaten, nor have I.
– Jane has not eaten, nor has John.
– Jane had not eaten, nor had they.
– Jane cannot swim, nor can I.
– Jane will not come, nor will John.
– Jane should not go, nor should we.

For

We use ‘for’ to:
– connect 2 clause where the second clause is the reason for the first clause (usually used in the past or formal context)

They were certainly there, for I saw them.
= They were certainly there, because I saw them.
I believed her, for she would not lie to me.
= I believed her, because she would not lie to me.
(‘Because’ is a subordinating conjunction, not a coordinating conjunction.)

So

We use ‘so’ to:
– connect 2 clauses where the first clause is the reason for the second clause

We were bored with the movie, so we left.
My stomach was still painful, so I went to see a doctor.

Yet

We use ‘yet’ to:
– introduce a fact, situation, or quality that is surprising after what has just been said (surprising contrast).

It’s a small car, yet it’s surprisingly spacious.
He has a good job, yet he never seems to have any money.