一岁的英文是：One year old ，yearling 。

例句1：Many infants do not cut their first tooth until they are a year old. 翻译：很多婴儿到一岁大时才开始长牙。 例句2：He was adopted by his eldest uncle when he was just one year old. 翻译：他一岁时就出继给大伯父了。一岁的英文是：One year old ；两岁的英文是：Two years old ；三岁的英文是：Three years old ；四岁的英文是：Four years old ；五岁的英文是：Five years old 。一般我多少岁用语句 i am ... years old 来表示。