單項(xiàng)選擇題Since many insects have already become()to DDT, scientists have to look for some new insecticide

A.active
B.resistant
C.tough
D.gradual


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2.單項(xiàng)選擇題He()the medicine quickly and then drank some orange juice.

A.sucked
B.swallowed
C.licked
D.digested

3.單項(xiàng)選擇題While studying he was financially dependent ()his wife.

A.to
B.of
C.on
D.from

4.單項(xiàng)選擇題The water was so()that we could see the fish inside clearly.

A.transparent
B.obvious
C.apparent
D.visible