--The air pollution is terrible.
--It will be worse_______ we take action to protect the environment.
| A．if | B．unless | C．until | D．when |
There aren’t any___ between them.
| A．different | B．difference | C．more different | D．differences |
—do you surf the Internet?
—Once a week.
| A．How | B．How old | C．How often | D．How many times |
I’m_____ taller than he.
| A．more | B．a little | C．most | D．many |
Can you come to my party ____ Monday night?
| A．on | B．at | C．in | D．for |
We usually start the day ___ breakfast.
| A．on | B．at | C．for | D．with |