What is 뭐 하러? how does it differ from 뭐하러?

최선을 다해 보지도 않고 이게... What is 지도 않고? Please correct me if I'm wrong. 최선을 - noun meaning the best way 을 - object particle 다해 - action verb to perform 여 보 - auxiliary verb to try 보지도 않고 - I couldn't figure this out 이게... - 이것이 - the thing/fact 이-subject particle Can you also please translate it? Thanks

우기는 덴 장사 없구나. What is the use of 는 and 덴 here? Hi. May I ask what is the literal translation of this one. I tried translating it using papago and it says "there's no business in the rainy season. What I am confused is, let us say that 우기 is noun meaning rainy season, attached by 는 which is a topic particle, what is the use of 덴? As far as I know 데 is a bound noun, and a bound noun can not stand alone, it's either must be followed by a prenoun or a noun-modifying form. But as far as what I learned a noun-modifying form is formed through attaching -(으)ㄴ/는/(으)ㄹ to a verb then the noun being modified, but 우기 here is not a verb, right? based on what the papago's translation says.