She must have been pretty_____to fall for such an old trick.A．interestedB．gullibleC．enthus

She must have been pretty______to fall for such an old trick.（2011 -80)A．interestedB．shrew

Nancys gone to work but her cars still there. She_____by bus.（2010)A．must have goneB．shoul

He must have had an accident, or he _____ thenA:would have been hereB:would be hereC:s

She claimed to have been a victim of child _______.A) abuseB) awarenessC) insecurityD)

I have no idea who stole his wallet. It _____anyone.A. must have beenB. should have been

They must have been enjoying themselves there, or they______so long.A．can"t have stayedB．w