The word kesh (գէշ), which means “bad, evil,” is a little tricky when you try to use it to express some English ideas. This is something that a native speaker may realize quite easily, if his/her language is not already contaminated by the use of English.
Let’s start with someone who needs to go to the bathroom quite urgently. He or she tells you: Shad kesh lvatsaran bedk eh yertam («Շատ գէշ լուացարան պէտք է երթամ»). This is an almost literal translation of “I need to go to the restroom very badly.” It is literal, which does not mean that it is right.
First of all, “badly” is an adverb, while kesh is an adjective. If you hear shad kesh lvatsaran…, it actually sounds ridiculous: it would mean that you need to go to a “very bad restroom” (= not a good one).
Secondly, the word “badly” has two meanings. One of them is “very much, to a great degree.” You will immediately realize the problem: the word kesh does not have this meaning in any dictionary. Therefore, you need to express “badly” with a word that shows that meaning, according to the context.
In this case, the person should have told you: Shad bedk oonim lvatsaran yertaloo («Շատ պէտք ունիմ լուացարան երթալու»). This amounts to “I am in much need of going to the restroom.” As you will see, it is not word-by-word translation. But who said that you need to translate word-by-word?
The second use of “badly” that is worthy of an exploration is the case of the athlete that bends his or her ankle and says Shad kesh vnasvadz em («Շատ գէշ վնասուած եմ»), meaning “I am very badly hurt.” It almost sounds like there is also a “good” way to be hurt.
This would also be wrong on all counts, indeed: “badly” means “severely, seriously” in this context. In Armenian, you have three adjectives to choose: dzanr (ծանր, “heavy, grave”), khisd (խիստ, “severe”), and loorch (լուրջ, “serious”). Because you translate concepts, you can say dzanr vnasvadz em, khisd vnasvadz em, or loorch vnasvadz em, and be on the safe side. You may also use the adverbial forms dzanroren, khsdoren, or lrchoren, but it is not mandatory, especially in a colloquial environment.
In any case, even if you are in an emergency, think before talking. You may be better understood.