词汇运用。

1.              (没有一个) of us has been to the USA.

2.  Our solar system is only a            (部分) of the galaxy.

3.  Are we            (孤独的) in the universe?

4. Their light has traveled several years to            (到达) us.

5.  I hope to meet a            (真正的) astronaut one day.

6.  We are good friends because we like the            (相同的) things.

7.  What            (外国的) language have you studied recently?.

8.  People in China and            (国外) have given money to help poor children.

9.  He stopped going to school a            (少数) years ago.

10.  That            (听起来) interesting.

一船在静水中的速度为6m/s，要渡过宽度为80m，水流的速度为8m/s的河流，下列说法正确的是（　　）

A．因为船速小于水速，所以船不能渡过此河

B．因为船速小于水速，所以船不能行驶到正对岸

C．船渡河的最短时间一定为l0s

D．船相对河岸的速度大小一定为10m/s