Every possible means _______ been taken to prevent the river _________.
| A．have; polluting | B．has; polluted |
| C．has; from being polluted | D．have; being polluted |
Many of the students turned a deaf ear to his advice, they knew it to be valuable.
| A．as if | B．now that | C．even though | D．so that |
I really appreciate some time to surf the Internet. But I am too busy.
| A．to have | B．to having | C．have | D．having |
I failed in the final exam last tem. Only then the importance of studies.
| A．I realized | B．I had realized | C．had I realized | D．did I realized |
A great fire in our town last night and many people became homeless.
| A．broke through | B．broke off | C．broke out | D．broke down |
The country’s car industry is so strongly protected that foreign cars are seen there.
| A．immediately | B．rarely | C．correctly | D．similarly |