The Google translate tool is fine.
I'm pretty sure its one of the Google translate tricks (like with justin bieber) or maybe its you translating it couple of times till you used Arabic.
You need to understand that the translator wont be perfect , at least for now .
Because Google translate = literal translation. Meaning that it wont sound quite right in other language.
Still, i don't know hot you got ... "Your mother eats grass"..but you can relay on Google translate