I don’t know ....... to do.

Mr. Davis has not missed a single lecture ................ he started teaching.

The students had been studying lesson one and the teacher wanted ....... lesson two.

The teacher might have accepted my late essay if I ...... him yesterday.

I ......... for the lecture to start for almost an hour. I don't know why it is delayed.

Judy: I saw Mrs. Nora yesterday. Julia: Really? …… she still teach Computer Science?