日韩亚洲一区中文字幕,日韩欧美三级中文字幕在线,国产伦精品一区二区三区,免费在线欧美性爱链接

Everybody is afraid of quicksand(流沙). In the films, people fall into quicksand. They are pulled down and down. They disappear! No one sees them again!

What is quicksand? Can it really pull things down? No. It cannot. Quicksand cannot pull things into it. Quicksand is really loose(松散的)sand and a lot of water. The water makes the quicksand. It is different from the sand on the beach. A person can walk on the beach. A person cannot walk on quicksand. It is too loose.

Falling into quicksand does not hurt. It is almost like falling into water! Your body will go down. But then it will come up. People can float(漂浮)in quicksand. But they must not fight the sand. That would make them go down. They should move slowty until they float.

Quicksand is found in many places. It is found near the mouths of large rivers. The mouth of a river is where the river meets the ocean or the sea. Quicksand is also found on land. In some places the water stays on the land. It does not drain(排放)or dry up. If there is sand around, the sand gets very wet. Then it becomes quicksand.

Will you go down in quicksand? Yes, but not all the way. You will float. But you should float in clean water. Quicksand is too dirty!

1.If you fall into quicksand,      .

      A.you should move fast and try your best to get out

      B.you will be gone and no one will see you again

      C.it is nothing serious and don't be afraid

      D.you will be pulled down and down and then die quickly

2.A person cannot walk on quicksand because      .

      A.it is dangerous                                       B.it is too loose

      C.it will hurt him                                       D.it will pull him down

3.You can find quicksand      .

      A.in a river                                               B.in the ocean       

      C.in the sea                                               D.at the ends of large rivers

4.It is difficult to find quicksand in      .

      A.dry countries           B.China                    C.America             D.wet countries

5.People don't like to float in quicksand because it is      .

      A.hot                         B.cold                      C.dirty                  D.soft