1 表示“整岁”,直接用基数词或year,age,例如“他20岁”可表示为: 
He is twenty. 
He is twenty years old. 
He is a twenty-year-old man. 
He is aged twenty. 
He is at age twenty. 
He is at the age of twenty. 
He is twenty years of age. 
2 表示“在某人几十多岁”,用“in one's +基数词复数形式”,例如: 
他七十多岁。He is in his seventies.(从70岁到79岁之间) 
她五十多岁。She is in her fifties.(从50岁到59岁之间) 
还可以借助early,middle,late来表达得更明确一些,例如: 
那女孩今年二十二、三岁。The girl is in her early twenties. 
他今年十四、五岁。He is in his middle teens. 
她今年二十八、九岁。She is in her late twenties. 
3 表示“快满多少岁”用进行时或将来时,例如“他快满十八岁了”可说成: 
He is getting on for eighteen. 
He is going on eighteen years old. 
He willbe eighteen years old. 
It willbe his eighteenth birthday. 
4 表示“不满多少岁”,用副词barely,nearly,al- most,quite,yet,just等,例如“她不满十七岁”有以下几种说法: 
She is barely /nearly /almost seventeen. 
She is not quite /yet seventeen. 
She is just under seventeen. 
5 表示“差多久满多少岁”用介词off,例如: 
他差5个月就满19岁了。He is five months off nineteen. 
她再过3年就50岁了。She is three years off fifty. 
6 表示“超过多少岁”用介词past,例如: 
他已年过50。He is past fifty. 
他是一个过了中年的人。He is a man past middle age. 
那孩子两岁零两个月。The baby is two months past two years old.
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