Don't sigh over the small achievement. _____ , and I'm sure if you keep at it, you'll see the light at the end of the tunnel!
| A．Lookers-on see most of the game |
| B．Constant dropping wears away the stone |
| C．The world is your oyster |
| D．Lost time is never found again |
—What was it that caused the party to be put off?
—________ the invitations.
| A．Because Tom delayed sending |
| B．Tom delayed to send |
| C．That Tom delayed sending |
| D．Tom delayed sending |
The new technology，if ________ to farming，will help increase the grain output.
| A．applying | B．to apply |
| C．applied | D．having applied |
________ this way can we smooth the difficulty we are faced with now.
| A．Just in | B．After in | C．Just by | D．Only in |
There are eight tips in Dr.Roger's lecture on sleep，and one of them is：________ to bed early unless you think it is necessary.
| A．doesn't go | B．not to go |
| C．not going | D．don't go |
Not until I read your letter ________ the true state of the affairs.
| A．did I understand | B．had I understood |
| C．I understood | D．I had understood |