문법 문제를 보다보니까.. 비슷한 유형이라 답은 눈에 보이는데,, 왜 이게 답이 되는지 모르는 문제가 있어 올립니다.

보어자리처럼 명사가 들어갈수 있는 자리에, 명사 대신 명사절이 오는데,, 항상 명사절을 이끄는 접속사(that) 바로뒤에 또다시 부사절접속사가 나오는게 항상 답이 되더라구요.. 이유를 알고 싶어요..도와주세요.

What was more confusing was _______ , the jets did not seem to carry nearly enough matter or force to create the massive bipolar outflows.

a. even if the age dilemma could be resolved that

b. even if that age dilemma could be resolved

c. that even if the age dilemma could be resolved

d. that the age dilemma could be resolved

답(c)

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Another difference between the natural and social sciences is _______, social science research may begin with observation and only later develop a theory.

a. that natural science research is almost always governed by an explicit theory

b. while natural science research is almost always governed by an explicit theory

c. that while natural science research is almost always governed by an explicit theory

d. while natural science research that is almost always governed by an explicit theory

답(c)

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그리고 이건 또 다른 유형인데요..

As early as the fifteenth century, people ________ in what is now Kentuchy traded with people as far away as the Atlantic coast and the Great Lakes.

빈칸에 들어갈 말은 who lived인데 왜 to live는 안되는지 궁금합니다..

형용사절이나 to부정사구나 수식기능을 가지는건 마찬가지자나요..ㅠ

가르쳐주세요....ㅠㅠ 복받으실 거에요..