Sing to that Anime tune!

I really can't understand most of the words, least watched their anime! But once an anime fan, always an anime fan. Here are some featured Anime OST which I personally haven't watched yet, but i simply loved the tune despite randomly hearing it somewhere. =D

First off, here's a kawaii song from the anime Chobits, Let me Be With You... (Chiii~)

Next off , here's the full version of I say YES! from the anime Zero no Tsukaima. Honestly this anime attracted me. I'll watch in the future and hopefully make a review about it! ;)

FTW?! It's an Ecchi!? I Didn't knoooooowww!!! x_x"

Then there's Hayate no Gotoku from Hayate The Combat Butler anime. What a title lol! XD

And lastly, errr.. I did watch this anime, but heck I wanna share the song to you guys, you got a problem with that!? XD Here's Arigatou from the anime Kyou Kara Maou! (God Save Our King!) I sing to this tune without knowing what it really means. =))