Every possible means ________ to prevent the air pollution，but the sky is still not very clear.
| A．were using | B．have used |
| C．has been used | D．was used |
－I didn’t watch the program “Where are we going, Dad?” yesterday.
－I _______, either, if my father hadn’t reminded me.
| A．wouldn’t | B．didn’t |
| C．wouldn’t have | D．hadn’t |
— Joe, don’t forget to bring your laptop with you tomorrow, OK?
— Oh, thank you. I wouldn’t bring it if you _____ me.
| A．wouldn’t remind | B．haven’t reminded |
| C．hadn’t reminded | D．shouldn’t have reminded |
--What a journey! We’ve finally arrived!
--_____ an out-of-date train schedule, we would not have missed the train.
| A．Had we not used | B．Did we use |
| C．If we didn’t use | D．If we had used |
-- I spent three hours buying a train ticket at the railway station the other day .
-- Why ? You __________ one on the Internet or by phone .
| A．could have bought | B．must have bought |
| C．would buy | D．should buy |
The officer commanded that the supplies of food and clothes ______ to the flooded area.
| A．should send | B．be sent |
| C．were sent | D．would send |