1 . In the past four years, local education departments have trained about 40,000 football teachers , 8,000 of ___________ have obtained coaching certificates. （用适当的词填空）

2 . This aspect will be discussed further by Crane in the next lecture, ________ I mentioned just now.

A．whom

B．why

C．that

D．when

3 . The school has more than 970 middle and high school students, half of ________ are Chinese. （用适当的词填空）

4 . Mary有3个儿子，现在都在国外。（用定语从句）(汉译英)

5 . He attended Jane's wedding, together with his two classmates yesterday, ________ I had met before.

A．that

B．when

C．which

D．whom