Bob said he was going to join our club but he didn’t. He _______ his mind.
| A．can’t have changed | B．wouldn’t have changed |
| C．must have changed | D．should have changed |
We are confident that the environment ________ by our further efforts to reduce pollution.
| A．had been improved | B．will be improved |
| C．is improved | D．was improved |
Generally, students' inner motivation with high expectations from others ________ essential to their development.
| A．is | B．are |
| C．was | D．were |
If we ________ now to protect the environment, we’ll live to regret it.
| A．hadn’t acted | B．haven’t acted |
| C．don’t act | D．won’t act |
（2012浙江卷） Armed with the information you have gathered, you can_______ preparing your business plan.
| A．set out | B．set about | C．set off | D．set up |
We ______ to paint the whole house but finished only the front part that day.
| A．set about | B．set up | C．set out | D．set down |