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。
_____youunderstandthisrule，you‘llhavenodifficultyindealingwithsuchproblems.
Iwilldotheclearingifyousee_____thelunch.
Beingextremely_____tothecold，Idonotlikeskating.
Copernicusmaintainedthattheearth_____roundthesun.
Icanspeak_____German.