问题

Mary has two brothers, ________ are doctors.
A:both of they
B:both of whom
C:both of them
D:whom of both
B:both of whom
C:both of them
D:whom of both
正确答案是:
同类题型
No one but you knows your heart is racing, so take a breath and try to ________ down.[ ]
Mr. Hand really____ his students and regards them ashis children.
Hello, Mike. Long time no see, Where are you—Oh, not only my parent but also I __ Wuhan for a month.
Jim went to answer the phone __________ , Harry started to prepare lunch