Do you use a or an with words beginning h e.g. i am reviewing historical documentr document?

You use "a" before words beginning with "h" if the "h" is pronounced. If the "h" is silent, you use "an".

In your example, "historical" has a pronounced "h" sound, so you would use "a":

* I am reviewing a historical document.

Here's a breakdown:

* "a" before words with a pronounced "h": historical, happy, house, heavy, etc.

* "an" before words with a silent "h": hour, honor, honest, heir, etc.