Not until actually ________ with water shortage ________ appreciate the value of water to a region.
| A．facing; one can | B．faced; can one | C．faced; one cannot | D．facing; cannot one |
Evidence has been found through years of study______ children’s early sleeping problem likely to continue when they grow up.
| A．why | B．how | C．whether | D．that |
I must find out why＿＿＿＿so many students made the same mistake.
| A．is it that | B．was it which | C．it is what | D．it was that |
It was announced that only when the fire was under control to return to their homes.
| A．the residents would be permitted | B．had the residents been permitted |
| C．would the residents be permitted | D．the residents had been permitted |
Mum is coming. What presentfor your birthday?
| A．you expect she has got | B．you expect has she got |
| C．do you expect she has got | D．do you expect has she got |
— Do you think George has passed the driving test?
— No. If so, he ____ _his car to our college yesterday.
| A．would drive | B．drove |
| C．would have driven | D．had driven |