質問: that is why ~の文 that is why ~. の文は, (1)that is why ~ (2)that is the reason why ~. ※先行詞を省略しないで。 (3)that is the reason for which ~. ※that不可。前置詞+thatがダメだから。 そこで,(4)は,普通ではないでしょうけど,出来るのですか? (4)that is the reason that ~ for. ※前置詞を後ろに残して,関係代名詞thatを使う。 どうなのでしょうか?
回答: for は不用です。 ----that is the reason that one should never marry.