At what age do babies start to recognize that they are active agents?

婴儿什么时候开始认识到他们有主动影响力？

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In fact, most of the heavy metal chlorides could not be used as active agents.

实际上，大多数重金属氯化物不能作为活性剂。

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In fact, most of the heavy metal chlorides could not be used as active agents.

实际上，大多数重金属氯化物不能作为活性剂。

youdao