Usually pilots need about a decade of experience _______ they can be promoted to captain.
| A．after | B．before | C．then | D．when |
The medicine works more effectively _______ you drink some hot water after taking it.
| A．as | B．until | C．although | D．if |
-- Bob, you are absent-minded!
--- Oh, I’m sorry I _______ attention to you, Miss Shute.
| A．haven’t paid | B．wasn’t paying | C．am not paying | D．couldn’t have paid |
There was a teapot shaped like a duck, out of ____open mouth the tea was supposed to come.
| A．which | B．its | C．that | D．whose |
--- Mrs. Smith, please teach me how to draw on the computer today.
--- Oh, no._______. You have to get familiar with the keyboard first.
| A．It is never too old to learn | B．Think twice before you do |
| C．Learn to walk before you run | D．One today is worth two tomorrows |
. He told us that the girl was _______, so we went to save her.
| A．dangerous | B．in danger | C．a danger | D．endangering |