Well, if you are using a Mac, there is a built in spell check that works while you type. It underlines words that are spelled incorrectly. If you control-click, or right click if you have a 2 button(or more) mouse, you get a pop-up menu with suggested correct spellings. You can also add new words to the dictionary.
What I/We really need is a Grammar checker.....
What I/We really need is a Grammar checker.....