Question

请教：下面这一题选A没问题，但是能否选B？可数名词单数特指不是也可用that（=the one）替换吗？

Some children want to challenge themselves by learning a language different from ______ their parents speak at home.
A.what

B.that
C.which
D.one

Answer 1

这里有个介词，from,因此是介词宾语从句，不是代词的考点

在宾语从句里，speak 在这里是及物动词，缺少宾语，只能用，联系代词what 充当
而that 你要是理解为代词，久无法连接句子了

如果理解为连词，则必须在不缺成分时候使用

因此，只能用what,不能用that

追问

这里把that=the one 即the language，后面their parents speak at home是省略了引导词的定语从句。能否这样？

追答

你用了，the one,做定语从句的先行词，是可以的

但是，the one that,的that 是关系代词，现行次是the one,你不能直接就用that 做先行词

我估计你的疑问，就在这里，你想直接用that 做先行词？

追问

你的意思是that
什么情况下都不能做先行词？对吗？
但是代词也是可以做先行词的，如：He who laughs last laughs best.

追答

all,，those 可以做先行词

that 不可以，因为那会自己和自己过不去，谁知道他是做先行词，还是关系代词？
第二，就算可以，前面有介词了，你见到from that that 这样的，不觉得怪吗？

Answer 2

以下都是正确的表达
1 Some children want to challenge themselves by learning a language different from the one that / which their parents speak at home
2 Some children want to challenge themselves by learning a language different from the language that / which their parents speak at home
3 Some children want to challenge themselves by learning a language different from what their parents speak at home
------ 你注意比较一下，然后你就明白了。

Answer 3

what = the one that/which

所以BCD都不完整，都不能选