Class regulations state _____ is the last to leave the classroom _____ off all the lights.

 I ________ thank you too much for all your help to my son while we were away from home.

Many people in China have never dreamed of ______ a chance for them to learn to drive after their retirement.

.—I can’t find Mr. Smith.  Where did you last see him this morning?—It was in the hotel _______ he stayed.    

He ____ in the north, but now he ____ here．