He‘sworkinghard_____.
B
for fear (that)“惟恐，以免 ”，引导的从句用虚拟语气 should+动词原形， should 可省略。 lest 意思及用法类似。
Thosepeople_____ageneralunderstandingofthepresentsituation.
_____alltherepresentativesstillnotthere，themeetingwaspostponedforseveralhours.
Childrenwhoareover-protectedbytheirparentsmaybecome_____.