We all feel it is Jack as well as his wife that ________ for their son's bad performance at school.

(2012·全国卷Ⅱ)Sarah made ________ to the airport just in time to catch her plane this morning.

This important lesson by Professor Wang teaches primary students how to ______ themselves from danger.

The man in black is _______ my lifeguard. He is also my close friend.

The number of the employees has grown from 1,000 to 1,200.This means it has risen ________ 20 percent.