英语语法中定语从句的问题

英语语法中定语从句的问题
1、Is this factory ______ the foreign visitors visited last week?
2、Is this the factory ______you once visited?
3、Is the factory ______you once visited?
A、where B、which C、the one D、that
2、B 3、C
能说出原因吗?

1 定语从句缺少先行词,This factory is ___ the foreign visitors visited...同时先行词在定语从句中做visited的宾语（关系词可省略）,填the one.
2 定语从句有先行词the factory了,只缺少关系代词,在从句中做visited的宾语,填which和that均可.
3 The factory is ____ you visited...缺少先行词,定语从句却宾语,填the one.
——————————————————————————
The day he has looked forward to _____at last.
请注意he has looked forward to是定语从句,先行词是the day,在定语从句中做宾语(关系词被省略),即
（他盼望的）那天,来了.
The day (that he has looked forward to) came at last.句子的主干是The day came at last.
懂了吗?