Yes, I'm going to be incredibly anal. But these things have been
annoying the Hell out of me ever since I finally got them right myself.
Anyways, here are some commonly broken grammar rules that I seem to be
finding here a lot.

  "Your" and "You're"
-Your: possessive form of "you". Ex.: "I'll always be _your_ friend."
-You're: contraction of "you are". Ex.: "_You're_ my friend."

  "Their", "They're", and "There"
-Their: possessive form of "they". Ex.: "That's _their_ property."
-They're: contraction of "they are". Ex.: "_They're_ not going to that."
-There: indication of some place. Ex.: "Don't go _there_."

  "Its" and "It's"
-Its: possessive form of "it". Ex.: "He's following the monster back to
_its_ cave."
-It's: contraction of "it is". Ex.: "_It's_ a nice day today, don't you
think?"

  Another thing: try not to switch back and forth between present and past
tenses when writing. It's very grating. Sorry to do this to you....

>From Andrew Huang, Taiwanese-American-German-Scot Harvard Student :P
Brought to you by his computer, Oddzilla
Oddzilla says, "Ryouga and Ukyou! Ukyou and Ryouga!"
http://www.hcs.harvard.edu/~alhuang
Kurimoto Shiro's manager, DBTFH