12. The problem wasn’t_______hard. The little girl worked it out quickly.
| A．that | B．much | C．enough | D．a little |
Using his hybrid rice, farmers are producing harvests ________________ before.
| A．as large twice as | B．twice as large as |
| C．twice larger as | D．as large as twice |
The situation is getting worse. We must __________ the trouble _____________.
| A．keep; spreading | B．prevent; spreading |
| C．stop; to spread | D．protect; to spread |
___________ was no doubt __________ someone had broken into the store the day before.
| A．There; that | B．There; whether | C．It; that | D．It; whether |
You __________ have told him my comment on him. Now, he is very angry with me.
| A．needn’t | B．couldn’t | C．shouldn’t | D．mustn’t |
--- I wonder if I could use your camera this afternoon.
--- ________________. I’m not using it recently.
| A．Sure, go ahead. | B．I would rather you do. |
| C．Yes, indeed. | D．Why not borrow? |