本题出自TPO32 Plant Colonization

原句案例

Pioneer species – those that occur only in the earliest stages of colonization – tend to have high rates of invasion because they produce very large numbers of reproductive propagules (seeds, spores, and so on) and because they have an efficient means of dispersal (normally, wind).

词汇讲解

pioneer species n. 先锋物种

reproductive propagules n. 繁殖体

spores n. 孢子

dispersal n. 分散，疏散

句子分析

句子结构

主句+分句1（定语从句）+分句2（原因状语）+分句3（原因状语）

主句：

Pioneer species tend to have high rates of invasion

分句1：that occur only in the earliest stages of colonization

分句2：because they produce very large numbers of reproductive propagules (seeds, spores, and so on)

分句3：because they have an efficient means of dispersal (normally, wind).

参考翻译

先驱物种——只出现在殖民的最初阶段——它们能高效的入侵，因为它们可以产生大量的生殖繁殖体 (像是种子，孢子之类) 并且它们有一种高效的传播方式 (正常情况下，是风) 。

原题解析

5.Which of the sentences below best expresses the essential information in thehighlighted sentence in the passage (paragraph 2)? Incorrect choices change themeaning in important ways or leave out essential information.

A.The seeds of pioneer species are usually carried by the wind to fertile sites, where theyreproduce very efficiently.

B.Pioneer species are successful invaders because they produce lots of seeds that aredispersed effectively.

C.Pioneer species produce their largest numbers of propagules during the earliest stages oftheir colonization.

D.Pioneer species reproduce very quickly and efficiently because they produce very largenumber of seeds.

原句强调了先锋物种入侵速度快的两个原因，一是能够产生大量可繁殖的种子，二是拥有有效的传播途径。原句和fertile sites没有关系，A丢失主句信息；C没有提到种子的繁殖力; D把并列原因概括为原因之间的因果关系。