1.选d.where
there are cases where speech has started late in a child who eventually turns out to be of high IQ.很多情况下,说话晚的孩子是高智商.
句子中,where 相等于“in which cases”
2.选a.to take
take the third place:获得第三名
become是“成为”之意,可以说become the third place winner,后面的名称必须是“人”
3.选b.that
that.是put forward的宾语从句,是介词forward 要求的.
译文：消息传来说,更多的高中毕业生将要被大学录取.
4.选c.those who
译文：我们将支持哪些承诺志愿来帮我们解决难题的人们.
be for:支持； be against:反对
5.选c.what
after what seemed half an hour,是after+what引导的宾语从句构成的介词短语.what 在从句中作主语,同时又是从句的引导词,“似乎在半个小时之后”.
再举个类似的例子：Your success depends on what you do.“what you do”就是on 的宾语从句