Question

Without facts, we cannot form a worthwhile opinion for we need to have a factual knowledge ________ our thinking.

A．which to base on	B．which to be based on
C．on which to be based	D．on which to base

Answer 1

D

试题分析：考查定语从句：句意为:没有事实，我们就不能形成有价值的观点，因为我们的思考必须以真实的知识为基础。upon which to base our thinking是动词不定式短语作定语，该短语中介词必须放在which前。 答案是D
点评：定语从句的考查主要集中在句子成分的分析。如果从句中缺少主语，宾语，表语定语使用关系动词。如果从句很完整，则使用关系副词。