单项选择题

If there were no trees ______.

A．the land would became fertile
B．heavy rains would clean the tropics
C．the rich top soil couldn't be held
D．there would be no agriculture
<上一题 目录 下一题>
热门 试题

单项选择题
According to the passage,______.
A．early man did not know how to make use of trees
B．tree are not as useful now as they were in the past
C．trees were more useful in the past than they are now
D．men have always found trees useful
单项选择题
Top soil means ______.
A．useless soil
B．soil found under the earth
C．soil on the surface of the earth
D．dry soil which is found in the desert
相关试题