1.  I could derstand .

2.  Babies who can't talk can pornt at think .

3.  I can communite with my America friend in English.

4.  We can controll the pollution of the water.

5.  We can not imange the world would be without water.

6.  We can advice other people not to waste fresh water.

7.  I can't concetrate on my studying.

8.  Post offices can privide some people to deal with these greeting cards.

9.  We can ralex by listening to the music.

10.  We can arrival in Beijing by train from Shanghai in one day.