定语从句Is this factory

不行， 不能还原为This is factory __________ some foreign friends visited last Friday. 这样有语法错误，factory是可数名，没有了this factory，那就要加冠词或复数。

是可以的。但是这种题一般都不会考，因为答案ACD都对的。选择题一般是选的最佳答案。the
one
后面省略了that/which。既然是选择题，D答案既是特指也省略了that/which，所以综合一下，还是这个更好一些。

你仔细想想看Is
this
factory
_正确变为This
factory
is
如果想你那样变成This
is
factory
就有问题factory是个可数名字前面应该有不定冠词a、an\定冠词the

the
one
是this
factory的同位语，此题不能变为陈述This
is
factory--,否则题干应为Is
this
the
factory--

the
one
是先行词
陈述语气是：This
factory
is
the
one
that
some
foreign
friends
visited
last
Friday.
that
可省略

扩展阅读：it says that china ... this is the place where ... this application fa ... this is what i disagree ... it is believed that ... it is that 强调句用法 ... it is the time that ... it is amazing that ... i am afraid that i can t ...