A. Where B. Where must C. Where can D. Where need
A. How, do B. What, make C. What, do D. How, make
A. mustn't dust B. not dust C. needn't dust D. mustn't dusted
A. need B. Must C. Need D. must
A. Do, off B. Don't, on C. Don't, off Do, on
A. untidy B. tidy C. clean D. clear
A. Don't dirty B. Don't clean C. Don't clear Do clean
A. Do come B. Don't C. Don't come Do go
A. Don't open B. Don't close C. Do open Do close
A. Please B. Air C. To air D. Airing
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