Use of Conjunctions
Conjunctions are words that join different kinds of grammatical structures. They connect words, phrases or sentences and are used to give more information about time, place, persons and things, but also give reasons, conditions and express contrast.
Conjunctions of Time
when, as, until, till, after, before, since, while, at first, but then
Janet was in her room when her mother called.
He waited until she came.
After Peter had had dinner, he read a book.
Conjunctions of Place
He didn't know where he had put his purse.
Conjunctions of Reason
because, therefore / that's why, why, in order (that)
He couldn't help them because he didn't have any time.
She was ill, and that's why she couldn't go to the party.
Conjunctions of Contrast
This city is nice to visit, but I wouldn't like to live there.
Conjunctions of Condition
if, unless, even if, in case (that)
Take your umbrella with you in case it starts raining.
who (persons), which (animals, things), that, whose
This is the man who / that won the race.
Is this the car which / that he bought last summer?