but
You use but to introduce something that contrasts with what you have just said.
used to link clauses
But is usually used to link clauses.
It was a long walk but it was worth it.
I try to understand, but I can't.
You can put but at the beginning of a sentence when you are replying to someone, or writing in a conversational style.
‘Somebody wants you on the telephone.’ – ‘But nobody knows I’m here.'
I always thought that. But then I'm probably wrong.
used to link adjectives or adverbs
You can use but to link adjectives or adverbs that contrast with each other.
We stayed in a small but comfortable hotel.
Quickly but silently she ran out of the room.
used with negative words to mean ‘only’
But is sometimes used after negative words such as nothing, no-one, nowhere, or none. A negative word followed by but means ‘only’. For example, ‘We have nothing but carrots’ means ‘We only have carrots’.
John had lived nowhere but the farm.
He cared about no one but himself.
meaning ‘except’
But is also used after all and after words beginning with every- or any-. When but is used after one of these words, it means ‘except’. For example, ‘He enjoyed everything but maths’ means ‘He enjoyed everything except maths’.
There was no time for anything but work.
Could anyone but Wilhelm have done it?