问题
选择题
He has two sons, _____ work as chemists. [ ]
A. two of whom
B. both of whom
C. both of which
D. all of whom
答案
答案:B
He has two sons, _____ work as chemists. [ ]
A. two of whom
B. both of whom
C. both of which
D. all of whom
答案:B