How to make Firefox spell check english language?

Question

My Firefox spell checks my native language, but I don't use that language too much. How can I make it spell check English?

Answer 1

I use British English Dictionary together with Dictionary Switcher. The switcher allows me to easily switch between English and my native language.

Another way if you don't want to use addons is to download the English version of Firefox and use that instead of the one localized for your language.

Answer 2

Well, there's English on this list. Unfortunately, the US English which I'm using isn't too good. Large number of words are missing.

Answer 3

This is all you need:

United States English Spellchecker

There are other languages available as well.