—You seem familiar with Mr. John?—Of course, we________ together for three years in the 1990s.have worked B. had worked C. are working D. worked
— I’d like to go to the cinema with you, Dad. — Sorry, my darling, but the film is ___________for adults only.
These mistakes are very___________ among students, so we’re not surprised if you also make such mistakes.
If anyone happens to drop in while I am out, _________ him or her leave a message.
Though I’ve tried very hard to improve my English, by no means ___________with my progress.
Science and technology have in important ways contributed to the improvement of agricultural production.