If only

'Only' can be placed after if and indicates hope, wish or regret according to the tense used with it:

a) if only + Present Indefinite / Future Indefinite – to express hope

If only he comes in time (= we hope he will come).

If only he will listen to her (= we hope he will be willing to listen).

b) if only + Past/Past Perfect – to express regret

If only he didn’t drive so fast. (= we are sorry he drives so fast)

If only you hadn't said that. (= we are sorry you said that)

If only I knew it for sure.– Ах, если бы я была в этом уверена (сейчас).

If only I had told her the truth. – Ах, если бы я сказала ей правду (в прошлом).

c) if only + would can express regret about a present action as an alternative to if only + past tense (it has the same meaning as wish + would).

If onl y he would drive more slowly.(= we are sorry that he isn’t willing to drive more slowly).

I wish

Wish expresses present, future, and past situations.

Here is a summary of patterns using wish:

I wish he came. – Хорошо бы он пришёл.

I wish you knew him. – Жаль, что вы его не знаете.

I wish you had come. – Жаль, что вы не пришли.