Question

【题目】This is the factory we visited last week.

Answer 1

【答案】which/that/省略
【解析】句意：这是我们上周参观的工厂。“____________we visited last week”是定语从句修饰the factory，从句中作宾语，指物，用关系代词that或者which或者省略。故填that/which/省略。