[ Grammar ]
Scientists think there ________ at least five mass extinctions in Earth’s history.
A. will be
B. are
C. have been
D. has been
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Past Simple - Present PerfectVerb AgreementPassive Voice and ModalsPresent Perfect and Present Perfect Progressive TensesModal Auxiliaries and Similar ExpressionsModal AuxiliariesGrammar - Collective NounsPresent Simple Positive and NegativeGrammar - used toSentence LabelingOther quiz:
Clause Markers TOEFL Grammar › ViewComplete the sentence with the best clause marker:
A warrior ______ saw an enemy approaching might send a smoke signal.
A. which
B. that
C. whom
D. who
Tag Questions › View
Georgianella ____________ her phone after 6pm, does she?
A. did not answer
B. does not answer
C. can not answer
Vocabulary › ViewWhat is the antonym for “abridge”?
A. Expand
B. Shorten
C. Elaborate
D. Clarify
Grammar › View
Have you ever ________ to China?
A. went
B. go
C. been
D. gone