原句案例：

　　Indeed,if you take baby tree swallows out of a nest for an hour (feeding half the set and starving the other half), when the birds are replaced in the nest, the starved youngsters beg more loudly than the fed birds, and the parent birds feed the active beggars more than those who beg less vigorously.

　　词汇讲解：

　　tree swallow n. 双色树燕，白杜燕

　　youngster /'jʌŋstə/ n. 小孩子，年轻人

　　vigorous /'vɪɡərəs/ adj. 精力充沛的;有力的，猛烈的

　　结构划分：

　　Indeed, (if you take baby tree swallows out of a nest for an hour) (feeding half the set and starving the other half),(when the birds are replaced in the nest), the starved youngsters beg more loudly than the fed birds, and the parent birds feed the active beggars more than those (who beg less vigorously).

　　深度分析：

　　这句话的主干其实就是后面的一个并列结构，A and B

　　the starved youngsters beg more loudly than the fed birds, and the parent birds feed the active beggars more than those (who beg less vigorously)

　　修饰一：(if you take baby tree swallows out of a nest for an hour) ，从句

　　中文：如果你把小的双色树燕拿出鸟巢一小时

　　修饰二：(when the birds are replaced in the nest)，从句

　　中文：当这些鸟被放回鸟巢时

　　修饰三：(feeding half the set and starving the other half)，非谓语动词

　　中文：喂养一半，使另一半挨饿

　　修饰四：(who beg less vigorously) ，从句

　　中文：乞叫没那么大声

　　参考翻译：

　　确实，如果你把小的双色树燕拿出鸟巢一小时(喂养一半，使另一半挨饿)，当这些鸟被放回鸟巢时，挨饿的雏鸟就会比喂饱的鸟叫得更大声，它们的父母也会喂积极的乞食者要多于那些不积极的。

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