定语从句1.This is the place ___ he lived in his childhood.此处为什么填

1.This is the place ___ he lived in his childhood.
此处为什么填 where ,而不填 that
定语从句中需要关系副词作状语,所以填where.其它情况：
This is the place （which/that/不填）he lived in his childhood （in）.
This is the place （in which）he lived in his childhood.
2.This is just the place ___ I'm longing to visit these years.
为什么填 that ,而不填 where
关系词在从句中作及物动词visit的宾语,所以用关系代词that.
解惑：先行词被just the修饰时,关系代词不可以用which,另外,这里作宾语的关系代词也可以省略.
3.The train was crowded and I had to get into a carriage ____ there were already seven other people.
为什么填 where ,而不是 that
定语从句中还是需要状语（在车厢里）,所以用关系副词where.
延伸：介词+关系代词=关系副词,所以,这里也可以用in+which,但不可以用that,因为,紧跟介词的关系代词只可以用which.
4.The science of medicine ,______ progress has been very rapid recently ,is perhaps the most important of all the science .
为什么填 in which ,而不填 of which
在非限制性定语从句中,也需要状语（在医学领域中）,刚好介词加关系代词等于关系副词,所以选择in which.

告诉你一个方法：你把先行词带到句子中，如果能直接放就填关系代词（that ，Which），如果还要加东西，就是关系到词（介词 Which ，when，where，why）百试百灵，治标治本

1 he lived in the place
in his childhood. 从句里还少一个介词in，原句那个in是和 the childhood 一起的
2 I'm longing to visit the place
visit 是及物动词，从句内部不缺介词，直接拿个关系代词来就行了，另外 先行词被just限定，也不能用which，只能用that了