Another part of the problem of learning language is you have to figure out what the boundaries are between the words.

学习语言的另一个问题是,你必须得确定单词之间的界线是什么

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Around eighteen months of age, they start learning words faster.

在大约十八个月大的时候,他们学习单词的速度加快

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What this means, if you average it out, is that since children start learning their first words at about their first year of life, they learn about nine new words a day.

如果你将这个数字平均一下,这意味着,儿童从一岁左右,学习第一个词开始,每天学会九个新词

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