In order to make our city green，______.
| A．it is necessary to have planted more trees |
| B．many more trees need to plant |
| C．our city needs more trees |
| D．we must plant more trees |
Though iPhone 4 is such a hit product, I won’t buy one unless its after service ______.
| A．was improved | B．gets improved | C．is improving | D．had got improved |
The 3G cell-phone must be of great use to ____wants to get the information through the
Internet quickly．
| A．who | B．whoever | C．whomever | D．whichever |
—Can you give me some advice on what I said just now?
—Sorry, my mind _____．
| A．has wondered | B．had wondered | C．is wondering | D．was wondering |
I’d appreciate _____ if you would like to teach me how to use the computer．
| A．that | B．this | C．it | D．you |
The government has to close those small factories to prevent the water of the river ______.
| A．polluting | B．from polluting | C．being polluted | D．polluted |