Can trees talk? Yes — but not in words. Scientists have reason to believe that trees do
communicate with each other. Not long ago, researchers learned some surprising things. First a willow tree attacked in the woods by caterpillars（毛毛虫）changed the chemistry of its leaves and made them taste so terrible that they got tired of the leaves and stopped eating them. Then even more astonishing, the tree sent out a special vapor—a signal causing its neighbors to change the chemistry of their own leaves and make them less tasty.
Communication, of course, does not need to be in words. We can talk each other by smiling, raising our shoulders and moving our hands. We know that birds and animals use a whole vocabulary of songs, sounds, and movements. Bees dance their signals, flying in certain patterns that tell other bees where to find nectar for honey. So why shouldn’t trees have ways of sending messages?
1．It can be inferred from the passage that caterpillars do not feed on leaves that          .
A．have an unpleasant taste
B．are lying on the ground
C．have an unfamiliar shape
D．bees don’t like
2．According to the passage, the willow tree was able to communicate with each other by       .
A．waving its branches              B．giving off a special vapor
C．dropping its leaves               D．changing the color of its trunk
3．According to the passage, bees communicate by        .
A．touching one another             B．smiling one another
C．making special movement         D．making unusual sound
4．The author believes that the incident described in the passage         .
A．cannot be taken seriously          B．seems completely reasonable
C．should no longer be permitted      D．must be checked more thorough