When I came into the classroom this morning, it ______ me that I had left my book in my dormitory.
As soon as the children _____ themselves in their seats in the classroom, the bell rang.
It was not until Bob took off his dark glasses that I _____ him.
Buses here are always crowded with passengers, so I prefer _____ there rather than take a bus.
------- Where did you find him? -------It was in the hotel _____ he lived.
The scientist ______ much of his time to increasing the rice production.