넌 좀 쉬어야 겠구나.  ---> You have to take of. / You need a break.

 => Corrected : The sentence is corrected grammatically.

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우리는 영화 보러 갈거란다. ---> We are going to watch a movie. ✔

우와, 해리포터요? ---> Wow, Harry potter? ✔

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