[ Grammar ]
Listen! I (think)————- someone (knock)———at the door
A. thinking – knocking
B. think – knock
C. think – is knocking
D. think – knocking

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Conjunctions, Interjections and DeterminersModals, Conditionals, and Clauses- Defining, Non-definingReported Speech and Reporting VerbsGrammar : Structural Common ErrorsVerb Patterns / IngGrammar TOEFLPreposition and Word FormPast Perfect Tense and Past TensePhrase vs ClauseGrammar - ConnectorsOther quiz:
Understanding Product Packaging and Tenses › ViewShe always ______ her homework before dinner.
A. does
B. do
C. is doing
D. has done
Noun Clauses › View
It is urgent that she _____________ the natural gas bill immediately.
A. pays
B. is paying
C. pay
D. paid
Vocabulary and Grammar › ViewWhat would you say to express sympathy for an injury?
A. I’m sorry to hear that.
B. That’s your problem.
C. Why didn’t you be more careful?
D. You shouldn’t do that again.
Grammar › View
Although the alcohol level in beer ___ ranges from 4-7%, it can go as high as 15%.
a. usual
b. unusual
c. usually
