※ 질문하기질문내용
In the ancient practice of sending messages through a bearer, people would write secret messages in a substance that would only be revealed on plain paper through the use of a reagent. For example, lemon juice is normally transparent on paper, but when heated, it becomes brown and any message written with it can then be read. But a bearer could not deliver just a blank piece of paper, so the sender would write an ordinary letter in ink and write the secret message in the spaces in between the lines. The recipient would then have to treat the letter and read between the lines of the letter [빈칸 추론]

저 빨간부분이 해석이 잘안되는데요 수령자는 화학처리를 해야할것이다 그리고 편지의 줄사이에 [빈칸]treat(화학처리를하다)라는 뜻이있던데요빈칸1.to hide the real details.2.to read the real message제가 답을 1번했는데요 답이 2번이네요 -0-;;2번은 해석이 read read두번 들어가서 이상한것같아서 해석이 잘안되는데1번.2번 각각 넣어서 해석좀 부탁드려요 ㅠㅠ그리고 would then 이건 어떻게 해석되는거죠 -0-;;-----------------------그리고 2번문제는요what`s more, the technological advances needed in order to develop safe, non-pollution, affordable energysources will cost a lot of money.이것도 해석이 잘안되는데 게다가 과학기술의 진보는 필요합니다/ 안전,공해가없는 발전을하기위해서 알맞은 에너지 자원은 많은 돈이 지불될것이다아 뭔가 깔끔하게 해석이 안되는것같은데 특히 in order to 이쪽부터 자세히좀 알려주세요 ㅠㅠ