Since the new speed limits ______，the number of accidents in the area has fallen strikingly．
| A．were introduced | B．introduced |
| C．have been introduced | D．have introduced |
There might be life on other planets, but so far scientists haven't found enough ________ to prove it.
| A．evidence | B．relic | C．mystery | D．reception |
If you go there by ____train ,you can have quite a comfortable journey ,but make sure you get ___fast one.
| A．/; / | B．/; a | C．the; a | D．the ; / |
--Mom, guess what? I’ve won the 1st prize!
---Thisa celebration! Let’s go to prepare a party．
| A．helps out | B．works out |
| C．calls for | D．pays for |
--How dangerous it was !
---Yes, but for the passer-by’s quick action,the girl _____ .
| A．had been drowned | B．might be drowned |
| C．would have been drowned | D．must have been drowned |
--Remember the first time we met?
---Sure. You _____ in the supermarket.
| A．shopped | B．have shopped | C．had shopped | D．were shopping |