Our village isn't the small quiet place ——it used to be.

因为句中关系代词在定语从句中作表语,不管是人或物只能用that.
比如：He is not the man that he was when I first saw him.
附一个which that在定语从句中的区别吧：
只能用that的情况：
关系代词在定语从句中作表语,不管是人或物只能用that.
He is not the man that he was when I first saw him.
【他现在不是我第一次见他时那样的.】
当先行词即指物又指人时,多用that引导定语从句.
Look at the girl and the dog that are crossing the street.
【瞧正在过马路的那个女孩和那只狗.】
当先行词是有生命的动物或人时,宜使用that而不是which.
1.What's the name of the animals that jumps about?
【四处蹦跳的动物叫什么名字?】
2.Who is the girl that talked to you yesterday?
【昨天和你说话的女孩儿是谁?】
当先行词被形容词的最高级修饰时引导定语从句的关系代词只能用that,而不能用which.
This is the most interesting book that I've ever read.
【这是我所读过的最有趣的书.】
当先行词被all,something,anything,nothing,everything,little,much,the one,none等时,引导定语从句多用关系代词that.
1.The goverment has promised to do all that lies in its power to alleviate the hardships of people.
【政府承诺尽其一切力量减轻人民的苦难.】
2.When we see anything that happen on the island,we're so glad.
【当我们看到岛上发生的事情,我们都如此兴奋.】
3.Tom told his father all that had happened.
【汤姆把事情发生的全部情况都告诉了他的父亲.】
4.Pay attention to everything that I do.
【注意我做的每一件事.】
5.The teacher wants to teach us all that he knows.
【老师想把他知道的全部知识都交给我们.】
6.You must do everything that I do.
【我做的每件事你必须都做.】
当先行词被the only,the very,the first,the last,few,little,no,all,one of,the same等修饰时,须用关系代词that来引导.
The only thing that we can do is to give you some money.
【我们唯一能够做的就是给你一些钱.】
当主句中已有疑问词who或which时,要用关系代词that.
Which is the bik e that you lost?
【你丢失的自行车是哪辆?】
只能用which的情况：
在介词后面的关系代词用which而不能用that.即“介词+which（代物）”
1.The picture for which he paid $1,000 was once owned by a duke.
【他花了1000美元买下的画曾为一名公爵所拥有.】
2.The building in which Han Mei studied was very old.
【韩梅在里边学习的那幢大楼很旧.】
在非限定性定语从句中不能用that.
Crusoe's dog,which was very old now,became ill and died.
【克鲁索的狗,现在已经很老了,病死了.】
有两个定语从句,其中一个关系代词已有which,另一个宜用that.相反,如果其中一个为that,另一个宜用which.
1.Edison built up a factory which produced things
that had never been seen before.
【爱迪生办了一个工厂,生产过去从未见过的东西.】
2.Let me show you the novel that I borrowed from the library which was newly open to us.
【让我给你看看我从新开放的图书馆借来的小说.】
共同点：
当定语从句所修饰的先行词为物时,关系代词可用which或that.
1.In fact the Swede did not understand the three questions that/which were asked in English.
【事实上Swede并不理解三个被提问到的英语问题.】
2.Colour the birds which/that are flying.
【给那些正在飞着的鸟上色.】
3.The pen that/which I am using is quiet good.
【我正在使用的那支钢笔相当好.】
4.The film which/that we saw last night was wonderful!
【昨晚我们看的那部影片真棒!】