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2 варианта:

223 Has Mrs Nelson been teaching French for ten or twenty years?

Has Mrs Nelson been teching French for twenty years?

224 Are the windows cleaned once or twice a month?

How often are the windows cleaned?

225 He has been painting for fifteen years, hasn't he?

Has he been painting for fifteen years?

226 Is hot or cold water provided by the hotel 24 hours a day?

Is hot water provided by the hotel 24 hours a day?

227 Alexander Graham Bell invented the phone, didn't he?

Did Alexander Graham Bell invent the phone?