英语选择题~请给出答案说解析,谢谢

题目

英语选择题~请给出答案说解析,谢谢
18. Now there are many opportunities ______ you can show your talent in our school.
A. in which B. that C. which D. of which
20. Chris, what’s wrong with you? That’s the sixth cup of coffee you ______ today.
—Nothing serious, mum I just feel tired and sleepy.
A. have B. had C. are having D. have had
24. While Microsoft just started its exploration into tablet computers, Apple has decided to go a different way ______ its iPad smaller and easy to carry.
A. to make B. making C. made D. having made

答案

答案是 18 A in which 引导定语从句 并在从句中作状语
同位语从句前面的名词 不包括opportunity故 后面不是同位语从句
其实opportunity和situation等的用法一样 后面经常 用 in which 引导定语从句
20D.have had 现在完成时 表示说话时 动作已经完成
24A.to make .不定式短语 作定语