There are millions of websites on the Internet and there _______ a lot of useful _________on the websites.

Over 20% of the students at that school _____ the habit of smoking, which is beyond imagination.

. No teacher and no student  ______．

Only 16 percent of China’s area ____ covered with forests, so ____of us should protect trees. 

 I’ve spare ___ juice for you, and your half ____ in the refrigerator.