A three-year-old might need help in understanding that other children feel pain just as he does, and that hitting a playmate over the head with a heavy toy requires an apology.

一个三岁的孩子可能需要他人帮助，才能理解其他孩子也和他一样会感到疼痛，用玩具重重地打了玩伴的头是需要道歉的。

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A new study has found that most three-year-old children can remember a lot of what happened to them a year earlier, and these memories are still clear while they are 5 and 6, but by the time they are over 7, these memories become weaker rapidly.

一项新的研究发现，大多数三岁的孩子都能记得很多一年前发生在他们身上的事情，在他们5岁到6岁的时候，这些记忆仍然清晰，但当他们超过7岁时，这些记忆就会迅速变弱。

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In a study, researchers gave three groups of six-year-old children a difficult task to complete on a computer.

在一项研究中，研究人员给三组六岁的儿童安排了一项困难的任务，让他们在电脑上完成。

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Called Repevax, it has been given to all three year old children as a pre-school booster for nearly a decade and health officials point to its excellent safety record.

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But then he berated parents for coaching their three- or four-year-old children to give them that extra edge over the five-year-old competition.

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In both maintained nursery schools and nursery classes attached to primary schools, the ratio for three- to five-year-old children should be 2:26, or 1:24 where the headteacher also teaches.

BBC: Nursery