years old用英文怎么说
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"Years old" 用英语表达为 "year-old"。这种用法是将"year"作为形容词来使用，而不是名词。来源上，这种用法可以追溯到古英语时期，在那个时候，"year"作为形容词的用法是很普遍的。
例句:
"She is a 5-year-old girl." (她是一个5岁的女孩。)
"He is a 10-year-old boy." (他是一个10岁的男孩。)
"The dog is 3-year-old." (这只狗3岁了。)
例句:
"She is a 5-year-old girl." (她是一个5岁的女孩。)
"He is a 10-year-old boy." (他是一个10岁的男孩。)
"The dog is 3-year-old." (这只狗3岁了。)