将下面四个选项分别填在横线上，每项只能用一次
A、缓慢氧化 B、疏松多孔 C、受空气和水的共同作用 D、将铁器与空气隔绝
（1）铁锈蚀的条件______；
（2）铁锈蚀的过程______；
（3）铁锈的结构______；
（4）在铁器表面喷漆______．
（1）我们知道钢铁锈蚀条件是：同时与氧气和水接触．由题意可知，C选项符合这两个条件，故选C；
（2）钢铁锈蚀的过程，实际上是铁与空气中的氧气、水蒸汽等发生化学反应的过程，生成氧化铁，属于氧化反应．由题意可知，选项A符合这一特征，故选A；
（3）钢铁锈蚀的过程，实际上是铁与空气中的氧气、水蒸汽等发生化学反应的过程，生成的铁锈的主要成分是Fe2O3?xH2O，结构很疏松．由题意可知，选项B符合这一状态，故选B．
（4）我们知道钢铁锈蚀条件是：同时和氧气、水接触．给铁器表面喷上漆，既可隔绝铁与氧气接触，也可防水．由题意可知，选项D符合这一目的，故选D．
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| It rained for four days. Mike couldn't go out and 1 with his friends. His parents went to work and had to 2 the boy at home. They bought some 3 for him. But he didn't like to read them. He stood by the 4 and looked outside. The rain 5 this morning and Mike was happy. But it was wet outside. His parents didn't 6 him go out and play there. They 7 the boy to read a book. But when they left he began to play behind the house. 8 his parents came back for lunch. His mother found the boy was very dirty." Oh, dearf Bcalled out the woman. "Look at your 9 ! How dirty they are! When did you see I was so dirty . 10 you?" "But I didn't see you when you were young, mum. "said the boy. | ||||
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