[ Grammar ]
My sister didn’t leave the car key, so I couldn’t pick her up at the airport.
A. If my sister had left the car key, I could pick her up at the airport.
B. If my sister have left the car key, I would have picked her up at the airport.
C. If my sister had left the car key, I would have picked her up at the airport.
D. If my sister left the car key, I would pick her up at the airport.

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Modals - Have to or ShouldPast simple vs Present perfectSuperlative & Comparative AdverbsWill, Be going to, Present ContinuousTypes of Simple SentencesActive and Passive voiceRoot WordPresent Simple PassiveModal and Auxiliary VerbsImperative SentencesOther quiz:
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