How do u say and write i kill u in spanish?

Question

me n my friend r wierd n she said shes dead n i was watchin jeff dunnham n achmed so i was like cuz i kill u n i keep sayin i kill u n she says no so i wanna say it in another language

Answer 1

I kill you=Te mato

I'll kill you=Te voy a matar or te mataré

Answer 2

"I kill you"? In Spanish, it's:

"Te mato."