单项选择题

We can learn from the passage that the tired land has fully recovered ______.

A．when grasses and other plants appear again
B．when the treatment is given by nature alone
C．after it has been lying idle for ten years
D．after grasses and other plants have decayed again
<上一题 目录 下一题>
热门 试题

单项选择题
An ignorant farmer will make the land poorer______.
A．ff he lets dead leaves decay in the soil by themselves
B．if he makes the humus decrease after taking away his crops
C．by clearing away all the dead leaves
D．by burning waste plant material lying about
单项选择题
From this passage it seems that ______.
A．Newton was not a successful scientist until he published his works
B．Newton was a scientist with at least three theories
C．Newton's theory was not accepted because Hooke did not approve it
D．Newton did not publish his theories because he was too disappointed
相关试题