My neighbors used to give me a hand in time of trouble was very kind of them.A. itB. who

问题补充：

My neighbors used to give me a hand in time of trouble, was very kind of them.

A. it

B. who

C. that

D. which

答案：

A. it

B. who

C. that

(答案→)D. which

解析：非限制性定语从句修饰物时只能用which，该句子修饰a hand ，故选D。