As we know, physics ______ the science of energy
1. As we know, physics ______ the science of energy.
A.was
B.were
C.is
D.are
.标准答案：C
2. I__________my wallet when I was shopping in the store.
A.must have dropped
B.should have dropped
C.could drop
D.ought to have dropped
.标准答案：A
3. A house with a dangerous gas ________ can be broken into immediately.
A.split
B.leak
C.mess
D.crack
.标准答案：B
4. The politician says he will ________ the welfare of the people.
A.prey on
B.take on
C.get at
D.see to
.标准答案：D
5 They took ___ measures to prevent poisonous gases from escaping.
A.fruitful
B.beneficial
C.valid
D.effective
.标准答案：D
