How to Say "I Hate You" & "I Love You" in Japanese?

Question

How do you say "I hate you" and "I love you" in Japanese?

Also, if you know, when Japanese words have underscores in them, are those necessary or can you put a space instead?

Answer 1

I hate you

Kirai yo!

I love you

[dai]suki yo!

It's not an underscore, it's a chouon, and yes it's necessary. It's a vowel extender.  

Answer 2

anata ga dai kirai desu. (I hate you)

anata ga daisuki desu. (I love you) also aishiteru.

Answer 3

I hate you

Anata ga kirai desu. (daikkirai is loathe)

I love you

Anata ga suki desu (as in like a lot)

Anata o aishiteru (or aishitemasu  (ai) which means love  

as for underscores...i'm not literate enough.

Answer 4

I hate you;

watashiha , anataga daikirai desu

I love you;

itoshi teimasu

I hope I'm not wrong, TT.TT

<3