Listen ! Helen is singing in the next room.It ____ be Helen. She has gone to Beijing.

＿＿＿＿＿＿ shall we have to go? —— Another five miles

It is difficult to imagine his _______ thedecision without any consideration.

I rang you at about nine, But there was no reply.— Oh, that was probably ______ I was seeing the doctor[ ]

Only after my friend came ____.