• When do you use hyphens in numbers?

Incorrect: There are three-hundred-sixty-five days in a year.

Correct: There are three hundred sixty-five days in a year.

Use a hyphen when writing out the numbers twenty-one to ninety-nine in words. Do not use hyphens for other numbers.


Incorrect: France has a 35 hour working week.

Correct: France has a 35-hour working week.

Incorrect: The ten year old boy wanted to become an archaeologist.

Correct: The ten-year-old boy wanted to become an archaeologist.

Use hyphens only when the number functions as an adjective phrase.


  • it’s OR its?

Incorrect: The dog lost it’s bone.

Correct: The dog lost its bone.

Incorrect: Its under the chair.

Correct: It’s (it is) under the chair.

The confusion between it’s and its occurs because ‘s indicates possession, so English speakers naturally want to use it’s to mean ‘something belonging to it’. But it’s is only used when it’s a contraction of ‘it is’ or ‘it has’. Otherwise, it’s always its.