1. Some bat caves,like honeybee hives,have residents that take on different duties such as defending the entrance,acting as sentinels and to sound a warning at the approach of danger, and scouting outside the cave for new food and roosting sites. (A) acting as sentinels and to sound (B) acting as sentinels and sounding (C) to act as sentinels and sound (D) to act as sentinels and to sound (E) to act as a sentinel sounding 答案选B 我有个不理解的地方。解释说defending,acting,sounding和scouting并列,但是可以后面用两个and吗?不是只有最后一个用and吗?就像我说的“defending,acting,sounding和scouting”里面的“和”一样。 请高人指点,谢谢
[此贴子已经被作者于2008-11-7 15:21:53编辑过] |