forty · number /ˈfɔː.ti/Full view
A2 the number 40
Dictionary examples:

thirty, forty, fifty

He looks about forty.

Learner example:

There were about forty people. (Key English Test; A2; Polish)

(be) in your forties
B2 to be aged between 40 and 49
Dictionary example:

By the time I'm in my forties, I want to be running my own business.

Learner example:

The man was in his early forties and he looked to be a very important man. (First Certificate in English; B2; Basque)

the forties
B2 the years from 1940-1949
Dictionary example:

Most of these people were born in the forties.

Learner example:

So, I would like you to consider buying some English comedies, like those Ealing Studios [made] in the late forties and the fifties. (First Certificate in English; B2; Spanish)

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