专升本考试

【单选题】 To carry out a company's rules and regulations, administrative personnel must know ______.
A．to be firm
B．being firm
C．what to be firm
D．how to be firm

网考网参考答案：D
网考网解析：
know后接宾语how to be firm，意为“如何坚定不移”。 查看试题解析出处>>