9.a modern city has been set up in(what)was a wasteland ten years ago.
这是一个介宾从句.题中“what was a wasteland"相当于一个宾语,即”曾经是一个荒地的地方“.这与in the room 是同一个道理.
类似what I want is a pen
如果想用which 的话,句子可以改成a modern city has been set up in the place which was wasteland 10 years ago.这里的”which“引导的就是一个定语从句了,place在这里做定语从句的主语.
10.Peter is no longer( who)he was 2 years ago.
这里“谁”在表语从句中是做主语.
19.Do you still remember the days( which)we spent in Qingdao?
which=the days,充当定语从句中we soent的宾语
因为本身we spent就缺少成分啊,我们度过什么?
20 do you still remember the days(when )we spent the summer hilidays in Qingdao?
when不充当任何成分,引导从句
we spent the summer hilidays 并不缺少成分,成分完成,我们度过暑假