forty

柯林斯词典

1. NUM Forty is the number 40. 四十; 40
2. N-PLURAL When you talk about the forties, you are referring to numbers between 40 and 49. For example, if you are in your forties, you are aged between 40 and 49. If the temperature is in the forties, the temperature is between 40 and 49 degrees. 四十几 (指40至49之间的数字)
He was a big man in his forties, smartly dressed in a suit and tie. 他是一个四十几岁的高大男子，穿着西服打着领带，很精神。
3. N-PLURAL The forties is the decade between 1940 and 1949. 四十年代 (指某世纪40到49年)
Steel cans were introduced sometime during the forties. 钢罐是在四十年代的某个时候开始使用的。

I think she gets about forty thousand pounds a year .
She swims forty lengths a day .
She was a successful banker by the time she was forty.
The report notes that forty percent of lawyers entering the profession are women.
The average person in the street is a lot better off than they were forty years ago.