彼がいつか帰ってくるのかははっきりとは知らない。の英語

I don't know for certain when he will come.

I don't know for certain when he'll come back.

I'm not sure when he'll come back.

I don't know exactly when he'll be back.

I do not know for certain when he will come.

I am not sure when he will be back.

I am uncertain when he will come next.

I don't know for certain when he will arrive.

I don't know for certain when he will arrive.

I don't know for certain when he will come.

I don't know when he will come back.

I don't know when he'll come back.

I don't know when he will come back.

I don't know when he'll come back.

I don't know exactly when he will arrive.

I don't know when he is going to come back.

I don't know when he'll be back.

I don't know when he will return.

I am not sure when he will come.

I'm not sure when he'll come.

I don't know when he will return.

I don't know for certain when he will come.

I'm not sure as to when he will turn up.

I'm not sure when he'll turn up.

I do not know when she will come back.

I don't know when she will come back.

He didn't specify when he would return.

I don't know exactly when I will be back.

I don't know exactly when I'll be back.

I don't know exactly when I will be back.