what we saw proved again that oil and water()mix
问题描述：
what we saw proved again that oil and water()mix
答案是don't还是didn't 我认为是don't 因为是真理.但是我又被时态困扰.
答
don't
prove后就表示说的话已经和时态没关了 一切书-作家-理念都应该是现在时
因为prove(证明)的是理念油和水不能混合 而不只是只在刚才那一刹那油和水才混合