With an appropriate relative pronoun:
(1) ____ we all know, oil and water don't mix up. (2)This is the only dictionary ____ he often turns to for help.
【正确答案】：As;that
【题目解析】：【考点点击】本题考查定语从句中关系代词的选择。【要点透析】[《Asweallknow《意为“众所周知”,为习惯用语,As在此引导定语从句,指代主句内容,即“水与油不相溶”。在定语从句中,当先行项由 the only修饰时,关系代词用that
