20．Tell John not to leave the house unless he_____________that the lights .
| A．will make sure，turn off | B．makes sure，are turned off |
| C．will make sure，will turn off | D．makes sure，will be turned off |
He said, “ ____ a long way to school. ____ a long way to go yet before we arrive.”
| A．It is, It is | B．There is, There is | C．There is, It is | D．It is, There is |
It ____ Mike and Mary who helped the old man several days ago.
| A．was | B．were | C．are | D．had been |
____ is no difference between A and B.
A. It B. Where C. There D. What
Was it in the place ____ the last emperor died?
| A．where | B．that | C．which | D．in which |
It was simply for that reason ____ I wouldn’t tell him the truth.
| A．why | B．which | C．so | D．that |