seventy · number /ˈsev.ən.ti/Full view
A2 C the number 70
Dictionary examples:

sixty, seventy, eighty

This house was built seventy years ago.

Learner example:

It cost seventy pounds. (Key English Test; A2; Spanish)

(be) in your seventies
B2 to be aged between 70 and 79
Dictionary example:

Both my parents are in their seventies.

Learner example:

After some minutes, an old man in his late seventies opened the door and told us in his trembling voice that Daisy wasn't at home. (First Certificate in English; B2; Italian)

the seventies
B2 the years from 1970-1979
Dictionary example:

I grew up in the seventies.

Learner example:

The nineties is, indeed, a reverse of the seventies. (First Certificate in English; B2; Swedish)

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