After suffering an injury during the match against Federer, Nadal has required surgery ____ his right knee.
A. on
B. at
C. to
D. in

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Figurative Language VocabularyDirect and Indirect QuestionGrammar: Used to, Would, Be used to, Get used toArticles and PronounsVerb Forms and PrepositionsPossessive NounsGerunds + To InfinitiveArticles - rulesBasic GrammarPunctuationsOther quiz:
Grammar › ViewChoose the correct preposition to complete the sentence.
We are very excited __________________ our trip to Spain next week.
A. at
B. with
C. about
D. over
Present Perfect Tense › View
Thousand of whales … (migrate) to give births.
A. migrated
B. are migrated
C. have migrated
D. has migrated
Vocabulary and Grammar › ViewLots of animals are losing their natural … because humans are cutting the forests down.
A. habit
B. hobbit
C. habitat
D. habittat
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Which sentence does NOT use a colon correctly?
A. The coach quizzed the team on: techniques, strategies, and goals.
B. Snoopy, the dog created by Charles M. Schulz, once said this in a cartoon: “Yesterday I was a dog. Today I’m a dog. Tomorrow I’ll probably still be a dog. Sigh! There’s so little hop for advancement.”
C. Attention park users: Littering now carries a fine of two hundred dollars.
