.
—Would you like to stay for another two days?
—Sorry, I ____. One of my best friends is coming to see me.
| A．mustn’t | B．can’t | C．needn’t | D．ought not to |
Our professor told us that salt water _____ at a lower temperature than fresh water.
| A．is freezing | B．was frozen | C．freezes | D．froze |
Nowhere else in the world _____ more friendly people than in China.
| A．you will find | B．you can find |
| C．can you find | D．you may have found |
—Brad was Jane’s brother!
—_____ he reminded me so much of Jane!
| A．No wonder | B．Above all | C．No doubt | D．Of course |
Many people claim that they have seen UFO with their own eyes, _____ I personally doubt.
| A．when | B．where | C．that | D．which |
My idea is _____ we should go to help him out at once.
| A．what | B．when | C．which | D．that |