[ Tenses ]
We have been waiting for them.
A. Past Perfect
B. Present Perfect Continuous
C. Present Continuous
D. Past Continuous

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Modals › ViewI …………… clean the house after the party last week.
A. must
B. might
C. mustn’t
D. don’t have to
Subject Verb Agreement › View
A number of politicians ________ to a new bill.
A. agree
B. agrees