People have come to understand _____ prevents so many Americans from being as happy as one might expect.
| A．that it is why | B．what does it that | C．why it does that | D．what it is that |
Thank you for all your hard work last week.I don’t think we ______ it without you.
| A．can manage | B．could have managed |
| C．could managed | D．can have managed |
If I ______ plan to do anything I want to，I’d like to go to Tibet and travel through as much of it as possible.
| A．would | B．could | C．had to | D．ought to |
— Shall I give you a ride as you live so far away ?
— Thank you. _______.
| A．It couldn’t be better | B．Of course you can |
| C．If you like | D．It’s up to you |
If I ________ plan to do anything I wanted to. I’d like to go to Tibet and travel through as much of it as possible.
| A．would | B．could | C．had to | D．ought to |
— Do you know where David is ? I couldn’t find him anywhere.
— Well. He ______ have gone far –his coat’s still here.
| A．shouldn’t | B．mustn’t | C．can’t | D．wouldn’t |