其次，从历史活动课设计的原则、设计内容及课文结构三个方面来分析历史活动课的设计； 第三，从“如何备?”

Second, it analyses the design of the history activity from designing principles, designing contents and the organized structures.

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化学具有悠久的历史，事实上，人类的化学活动课追溯到无记录时代以前。

Chemstry has a long history. Actually it can be dated back to the era of no written-record.

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