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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His parents no longer worry about him. He has a good job and can live（）his own now.

A.at
B.by
C.on
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He（）the medicine quickly and then drank some orange juice.

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