单选题Water ______ be changed into gas, but it ______ be heated to its boiling point.Amust; canBmay; needn’tCcan; mustDneed; may

单选题
Water ______ be changed into gas, but it ______ be heated to its boiling point.
A

must; can

B

may; needn’t

C

can; must

D

need; may


参考解析

解析:
句意:水能够变成气体,但必须得它达到沸点时才可以。

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