30. He _____ his potential had it not been for his desire to meet new challenges.
| A．would never have realized | B．would never realize |
| C．never realized | D．had never realized |
Look out! Don’t get too close to the house roof is under repair.
| A．of which | B．which | C．whose | D．what |
Is this the factory you visited last week?
| A．that | B．the one | C．where | D．in which |
I have already told our class teacher that the windows of our classroom require .
| A．repairing | B．being repaired | C．to repair | D．repaired |
Can you tell me____ last year ?
| A．where does Mary work | B．where did Mary work |
| C．where Mary works | D．where Mary worked |
She won’t go to library tomorrow. ____
| A．So will I | B．Me, neither | C．Nor am I | D．Me, too |