请问,“一岁”翻译成英语是"one year old"还是"one years old"?

请问,“一岁”翻译成英语是"one year old"还是"one years old"? 请问,我一岁了,用英语怎么说:one year old ,还是one years old 1岁时,是 one years old 还是 one year old? 一岁是one year old还是one years old? 急! 他一岁了,翻译成英语时,year要加s吗 he is one year old he is one ---- old .横线上填year还是years old one years 英语口语中,“我21岁”是I am twenty first years old,还是twenty one years 请问是six-year-old还是six years old还是six-years-old?(这个空签名有个a ) Saran is 12 years(old,older).She is one year 请问:是a four years old boy?还是a four year old boy?正确 是FIVE YEAR OLD还是FIVE YEARS OLD