Question

As is known to all, theory is based on practice and _____ serves practice.

A．in hand

B．in turn

C．in return

D．in exchange

Answer 1

B

考查词组辨析。In hand在手头，在控制中 in turn轮流，反过来（作用于） in return 作为回报 in exchange 交换 本句意为，众所周知，理论建立在实践的基础之上，反过来服务于实践。