[ Tenses ]
When Carol _________ dinner, someone __________ on the door.
A. was cooking/ was knocking
B. was cooking/ knocked
C. cooked/ knocked
D. cooked/ was knocking

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Preposition FormPrepositions & Modal VerbsModal AuxiliaryActive-Passive VoicesFigurative LanguageProgressive TenseNo Excuse Words / Conjunction SOGrammar and SyntaxActive vs. Passive VoiceGrammar - too & enoughOther quiz:
Prepositions › ViewDavid is always _____ time.
A. in
B. on
C. with
Homonyms › View
Meet me in the back ___.
a. lain
b. lane