Michael ________ football regularly for many years when he was young.
| A. was playing | B. played | C. has played | D. had played |
Thanks to the policy, birth rates in the country_____ 2 percent annually for the past five years.
| A. have been risen | B. have been rising | C. are rising | D. are risen |
—Hello, I’d like to see Doctor Smith at 3 o’clock tomorrow afternoon.
—Sorry, but he ________ a patient at that time.
| A. will operate on | B. will be operating on |
| C. will have operated on | D. will have been operated on |