问题
选择题
This machine, _____ for many years, is still working perfectly. [ ]
A. after which I have looked
B. which I have looked after
C. that I have looked after
D. I have looked after
答案
答案:B
This machine, _____ for many years, is still working perfectly. [ ]
A. after which I have looked
B. which I have looked after
C. that I have looked after
D. I have looked after
答案:B