1. 과학자들은 우리가 종이를 재활용하는 것을 가능하게 만들 수 있다
원래답 : scientists can make it possible for us to recycle paper
제답 : scientists can make us be able to recycle paper

2.교통수단 앞에 관사 an를 안붙였는데
taking an airplane costs three times more money than taking an train

3. since comics appeared, 만화를 비판해 오는 사람들이 있다
원래답 : since comics appeared, there have been those who criticized comics
제답 : since comics appeared, there have been people who creticized those.

4. as를 빼먹었어요
거의 돌처럼 단단하지만 플라스틱 같은
the first people to discover these properties ten thousadn years ago had found a material that
was almost as hard as rock but behaved like a plastic

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