It's borderline reckless.

It's borderline reckless.

(그거는 무모한거나 마찬가지야.)

~그거는 미친거나 다름 없는 거야.

~그거는 죽는 거랑 다름 없는 거야.!

(이런 뉘앙스로 쓰고 싶으면 borderline 을 넣으면 될 듯)

border: 테두리, 경계

(national) border : 국경

border on : ~에 걸치고 있다, ~에 접하고 있다.

           (양이나 숫자에) 다다르다.

senior prank:  

A senior prank is a type of organized prank pulled by the senior class of a school, college, or university to cause chaos throughout the institution. The pranks are usually carried out at the end of the senior school year as a going away mark on the school, and in some cases have become something of a tradition

How about we buy crickets and set them loose 

in school ? (귀뚜라미 사거지고 학교에 풀까?)

That's borderline reckless. 

Anything with live animals is too much. 

(살아 있는 동물로 하는 어떤 것도 너무 심해.)

I thought the ending was too much.

(영화 같은 것의 엔딩이 너무 터무니 없다고 생각했다.)

That's good. But an even better idea would be to use glitter instead of balls.

(glitter: 장식용 반짝이) 

chest cavity: 흉강(폐가 차지하고 있는 공간)

space occupied by one's lung.

valve: (신체에 사용될 때에는) 판막

The day he got out, he decided he wanted to ride his bike.

(퇴원하자마자, 걔는 자전거가 타고 싶어졌어요.)

He could hurt himself and end up in worse shape than he started.

(타다가 잘못해서 다칠 수도 있고 퇴원할 때보다 더 안 좋은 상태가 될 수 있고요.)