Question

He lived in London for 3 months, during ________ he picked up some English．

[　　]

A．

this

B．

which

C．

that

D．

when

Answer 1

答案：B
解析：

during为介词，介词后面的引导词只能用which和whom；题中非限定性定语从句的先行词是3 months，所以用which来引导。