Now that you know a little bit about the japanese language, you will find alot of words which are used very often in anime. So I made a little list for you.
Abunai - Careful! It's a warning for someone to look out.
Ai - Love
Arigatou - Thank you
Baka - Idiot
Bishoujo - Pretty girl
Bishonen - Pretty (usually girlish) man
Chibi - Little
Chotto - a little. "chotto motte kudasai" - please wait a moment.
Daijobu - ok, healthy. "daijobu ka?" - Are you ok?
Doujinshi - fan made manga.
Ecchi - nasty but not explicit hentai. used on a person it means pervert.
Hentai - explicit pornographic work, both in anime and manga form. Used on a person it just means pervert.
Hidoi - terrible!
Kanojo - Girlfriend
Kareshi - Boyfriend
Mahou - Magic
Otaku - Someone who's obsessed with something (not necessarily anime)
Shoujo - little girl
Sugoi - great, wonderful
Totemo - completely
Ureshii - happy
Yakusoku - a promise usually between childs
Yaoi - hentai /ecchi work with homosexual content between males.
Yuuri - Yaoi with girls instead
Next time when you're watching anime you can look out for these words.