HIGH-GMAT第三题请教：

liushiyou

Just as plant species native to regions with browsing mammals evolved many natural antibrowser defenses, [U][/U] ----------------- B. humans in malarial regions have been evolving dozens of chemical defenses against malaria. --------------- 答案为A。请问： ---------------------------- 1.在什么情况下，主句前可以出现so之类的词？ 所给的解释为：A和B的结构与just as之后的句子的结构最相似，但B的时态不对，所以选A。 ------------ 2.此题如何选择时态？ ------------ 3.如果B中的“have been evolving”变为“have evolved”，是否也为正确答案？ -------------------- 谢谢！

maryland

关于这道题，只有一句话：Just as。。。，so。。。是固定搭配，而且是ETS喜欢出的考点，记住即可。[em06]

oddyuibe

agree with Maryland
我也见过一道这样的题目，就是考的
just as.........,so................
固定搭配

dl7801

1)  A do (does) sth., just as B do(does)
2)  just as A do(did,does), so B do(did, does)
3)  just as A do, so too  +  do(does,did) /are(is, were,was)/  +  B ......

maryland

以下是引用dl7801在2003-4-11 22:39:24的发言：
1)  A do (does) sth., just as B do(does)
2)  just as A do(did,does), so B do(did, does)
3)  just as A do, so too  +  do(does,did) /are(is, were,was)/  +  B ......

精辟，详细。加精华！[em06]