单项选择题

The passage is mainly concerned with the ______.

A．geographical distribution of plant and animal species
B．location and purpose of the pulvini
C．appearance of the mimosa
D．process that causes movement in the mimosa

<上一题目录下一题>

热门试题

单项选择题

The author mentions folding chairs in the first paragraph in order to ______.

A．settle a dispute
B．evaluate a claim
C．provide an illustration
D．point out a difference

单项选择题

According to the passage, when could people start using a maglev commerciaily

A．In 5 years.
B．In 10 years.
C．In 20 years.
D．In more than 20 years.