6. My father hasn't smoked cigarettes for a month. A. It's a month since my father last smoked cigarettes. B. It's a month ago that my father smoked cigarettes. C. It's a month that my father hasn't smoked cigarettes. D. It's a cigarette that my father smoked a month ago. 7. Having finished their work, the workers expected to be paid. A. The workers expected to be paid because they had finished their work. B. Having their work finishing, the workers expected to be paid. C. Having expected to be paid, the workers finished their work. D. Having been finished their work, the workers expected to be paid. 8. Mr. Brown bought this car five years ago. A. Mr. Brown started to buy this car for five years. B. It has been five years when Mr. Brown has bought this car. C. Mr. Brown has had this car for five years . D. It is five years ago since Mr. Brown has bought this car. 9. John used to write home once a week when he was abroad. A. John doesn't write home once a week any longer. B. John enjoyed being written home every week when he was abroad. C. John never forgot to write a weekly letter home when he was abroad. D. When he was abroad he remembered to write home every week. 10. I haven't enjoyed myself so much for years. A. It's years since I enjoyed myself so much. B. It's years since I have enjoyed myself so much. C. It was years since I had enjoyed myself so much. D. It has been years since I have enjoyed myself so much LM VÀ GIẢI THÍCH GIÚP EM VỚI Ạ ! GIÚP EM VỚI LM XONG NHỚ GIẢI THÍCH GIÚP RM NHA :333