10.Measles deaths have dropped 60% since 1999, thanks to (vaccinate) ______ drives.
举一反三
- I _____English in this school since 1999 . A: taught B: have taught C: teach D: would teach
- •My wallet is nowhere to be found. I _________ in the store. A: must drop it B: must have dropped it C: should have dropped it D: ought to have dropped it
- My wallet is nowhere to be found. I（）when I was on the bus. A: must have dropped it B: must drop it C: should have dropped it D: have dropped it
- My watch is nowhere to be found. I it when I was on the bus. ( ) A: have dropped B: must have dropped C: must drop D: can’t have dropped
- I my wallet when I was shopping in the store(). A: must have dropped B: B should have dropped C: could drop D: ought to have dropped