[ Modals ]
His number was busy all night – he ________been on the phone continuously for hours.
A. must have
B. could have
C. should have
D. might have

Random Topics:
Relative & ModalsPerfect Tenses of VerbsHave to/Has toPresent Simple and Continuous TensePrepositionNoun PhraseVerbs + Gerund or InfinitiveModals and Past ModalsIdiomsPreposition and Word FormOther quiz:
Conjunction › ViewQuan got wet yesterday ______ he forgot to bring his umbrella.
A. and
B. so
C. because
D. although
TOEFL Adjective and Adverb › View
Coastal areas . . . higher humidity levels.
A. are generally experience
B. experience generally
C. are experienced generally
D. Generally experience