the sight of the scene of war, my_____ race back more than 50 years to the dark days of 1940.

Eat less food _______ you want to put on weight

Electronic devices such as iPods and headphones can do great harm to our hearing if _______ improperly.

Haven’t you been to Beijing before—.I went there last summer.

The songs of Jay Chou are very popular _______ young people.