单项选择题
A.valid B.portable C.prosperous D.voluntary
What these young men were doing（）a threat to the safety...
单项选择题What these young men were doing（）a threat to the safety of the whole neighborhood.
A.constructed B.contracted C.constituted D.contributed
Doctors hope to（）a human heart into the patient within ...
单项选择题Doctors hope to（）a human heart into the patient within the next few days.
A.transfer B.transform C.transplant D.transport
The tension（）as the guest of honor was about to announc...
单项选择题The tension（）as the guest of honor was about to announce the winner.
A.mounted B.accented C.climbed D.raised
