[ Past Modals ]
“What about someone with a key? A member of staff, perhaps?”
“It ___ have been one of the staff as I’m the only person with a key.”
A. must
B. can’t

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Who vs WhomParticipal PhrasesClauses and ConjunctionSentence Fragments and Complete SentencesWill vs be going toand, so, but, becauseSimple Present and Present Continuous TenseHave to/Has toParallelism and Subject Verb AgreementSo....that... Such.......thatOther quiz:
Grammar › ViewThe restaurant will be closed _______ the end of the quarantine
A. until
B. while
C. from the moment
Coordinating Conjunctions › View
She is tired, _____ she is determined to finish her homework.
A. Despite
B. Furthermore
C. Although
D. Nonetheless
Vocabulary › ViewHe gave no hint that he was in pain.
A. purpose
B. clue
C. target
D. affair
E. wage
Modal Verbs of Certainty and Possibility › View
It ______ very easy for him to tell her.
A. couldn’t have been
B. mustn’t have been
