But As A Conjunction

As a conjunction

But, as a conjunction, is used to join contrasting ideas.

• Their front door was open, but nobody was at home.
• The rope was thin but it was strong.
• He is hardworking, but not clever.

As a preposition

But, as a preposition, can mean except after all, none, every, any, no etc.

• They are all wrong but me! (= — except me.)
• All but you loved me for money. (= All except you loved me for money.)
• Everybody came but John. (= Everybody came except John.)

The expression but for is used to express the idea of if something had not existed/happened.

• We should have enjoyed the journey but for the rain.
• He would have helped us but for having no money himself. (—except that he had no money.)

After but we usually use object pronouns. Subject pronouns are also possible in a formal style.

• Nobody but him would do a thing like that. (More formal: Nobody but he —)

Cannot but + infinitive

Cannot but + infinitive or cannot help but + infinitive is often used with the meaning of can’t help -ing.

• I cannot but admire your courage (= I cannot help admiring your courage.)

But meaning only

But, as an adverb, can mean only. This is very unusual in modern English.

• We can but try. (= We can only try.)
• He is but a boy. (= He is only a boy.)