题目

北京人过着群居生活的主要原因是（ ）①血缘关系的结合 ②工具简陋粗糙③人们头脑简单 ④生活环境险恶 A . ①② B . ③④ C . ①③ D . ②④ 答案：DThere was ________ could make Abraham Lincoln stop his fight against slavery. [　　] A．something whichB．anything that C．nothing thatD．nothing which