When you were young, especially before you turned 3, the eustachian tubes were very small and less able to keep germs out.

当孩子小的时候，尤其是三岁以下的儿童，耳咽管非常短，不能有效地将微生物阻隔在外面。

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When you were young, especially before you turned 3, the eustachian tubes were very small and less able to keep germs out.

当孩子小的时候，尤其是三岁以下的儿童，耳咽管非常短，不能有效地将微生物阻隔在外面。

youdao