A study ________ in the U.S.A. in 1977 showed that the chemical ASA in aspirin could prevent a stroke.
A. carrying out B. carried out C. working out D. worked out
—Let's go Dutch for this supper, OK?
—No，________this time, as a reward for all your help.
A．it's up to you B．it's my treat
C．let's talk about it D．it doesn't matter
At the United Nations Climate Change Conference, the UN Secretary General points out that，________， the climate situation will get worse and worse.
A．if not dealing with properly
B．unless dealing with properly
C．if properly dealt with
D．unless properly dealt with
—Who should be responsible for the accident?
—The boss, not the workers. They just carry the orders________.
A．as told B．as are told
C．as telling D．as they told
I can't thank you _______ much because without your help I _______ have won the first prize.
A．too; wouldn't B．very; shouldn't
C．that; might not D．so; couldn't
Had I known about this computer program, a huge amount of time and energy________.
A．would have been saved B．had been saved
C．will be saved D．was saved
