3. What is meant by "concert songs" in the seventh paragraph?
A)Songs sung by zebra finches at a concert.
B)Songs sung by male finches for female finches.
C)Songs sung by female fmches for male finches.
D)Songs sung by male fmches to many female finches.
4. What is NOT true of directed communication?
A)The sender of a message has a specific audience.
B)Male zebra finches sing to female finches.
C)Mothers talk to their babies，
D)Male zebra finches sing to themselves.
5. Which of the following can best reflect the theme of the passage?.
A)Chirping away.
B)Birdsongs as communication.
C)Zebra finches and their life.
D)Enjoying birdsongs.
答案与题解：
1. C 文章第一段的第二句告诉我们，雄性斑胸草雀只要注意到有雌性斑胸草雀听他唱歌便会改变声调。其他选项均不是该段所表达的意思。
2. A 选项B、C、D 都不是答案，因为文章的第五段说，有配偶的雌性胸草雀更喜欢她们配偶的歌声，而没有配偶的喜欢的听雄性斑胸草雀为雌性斑胸草雀的歌。
3. B 第四段提到…a male performing for a female audience， as if he was giving a concert. 所以，第七段中的concert songs 即指雄性斑胸草雀为雌性斑胸草雀的歌。
4. D 文章的最后一段解释了什么是directed communication，即，when the communicator， or sender， focuses the message for a specific audience. 该段又举了母亲对婴儿说话的例子，说明这与雄性斑胸草雀为雌性斑胸草雀的歌同属directed communication.
5. B 文章所涉及的研究旨在发现雄性斑胸草雀歌声是否会在不同的情况下发生变化，其结果是，它们在为雌性斑胸草雀唱歌时，会改变声调和速度。这就是说，它们的歌声实际上是一种交流方式。所以应选择B.