问题补充:
The man called his professor for help because he couldn’t solve the problem by .
A. herself
B. himself
C. yourself
D. themselves
答案:
A. herself
(答案→)B. himself
C. yourself
D. themselves
解析:herself她自己;himself 他自己;yourself你们自己,你自己;themselves他们自己。句意:这个人向他的教授请求帮助,因为他不能独自解决这个问题。结合语境可知下文反身代词指代的是前文的the man,男性,单数,故选B。