When ______ why he walked in ______ permission,he just______at us and said nothing 。
This course of study________to help those________to go abroad is popular with young people.
The flu is believed________by viruses that like to reproduce in the cells inside the human nose and throat.
He hadn’t paid for his water so the company had________it off.
In the last few years thousands of films________all over the world.
The manager thought________difficult to finish the task in such a short time.