Choose the correct answer

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26. While we ____ dinner, the guests arrived.
A. had B. were having C. have D. having

27. He wishes he ____ how to swim.
A. know B. knew C. knowing D. knows

28. She ____ when I called her last night.
A. sleep B. slept C. was sleeping D. sleeps

29. I wish I ____ that mistake.
A. didn't make B. don't make C. won't make D. hasn't made

30. She wishes she ____ play the guitar.
A. can B. could C. will D. should
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