The owners of many coal mines must measures which improve working conditions.A.t
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The owners of many coal mines must ________ measures which ________ improve working conditions.
A.take; tends to
B.take; tend to
C.make; tend to
D.have; tends to
试题答案
B
take measures采取措施；定语从句中的谓语动词的数取决于它所修饰的先行词的单复数形式。