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做 is usually used as verb. such as 做作业， 做事情 作 is usually used as noun. such as 作业 ，作风。 but sometimes 作 can also be used as verb. In this situation, 作 can be replaced by 做. for example, 做事=作事,做工=作工,做人=作人.

“做”表示具体动作，“作”表示抽象动作

做 and 作 is different mean in Chinese. 做 in english : do or to do , 作 in english : as In Chinese mean : As: abstract object used for or no physical activity, action is weak; to do: focus on specific physical objects or activities produced, action stronger.

簡單的說 做用于動詞 作用于動詞和名詞。