Which 和that同為關係代詞，都可指物，並且有時會覺得用that 也可以，用which 也沒錯。但在哪些情況下是隻能用that的呢？下面是小編為你帶來的只用that的`定語從句 ，歡迎閱讀。
一、注意先行詞：
1）先行詞是這樣的不定代詞：everything, anything, nothing, all, none, few, little, some（除something外）；
e.g: There seems to be nothing that is impossible to him in the world.
Note:先行詞指人，偶爾亦可用關係代詞who:
e.g: Any man that/who has a sense of duty won’t do such a thing.
2）先行詞受every, any, all, some, no, little, few, much等詞修飾。
二、先行詞受如下詞修飾：
1）被序數詞修飾：
e.g: The first English letter that I learned was A.
2）被形容詞最高階修飾：
e.g: This is the best movie that I have ever seen in my life.
3）被the very, the only, the first/last修飾
e.g: After the big fire, the old car is the only thing that he owns.
Note:先行詞指人，偶爾亦可用關係代詞who:
e.g: She is the only person that understands me.
三、先行詞前有who, which等疑問代詞：
e.g: Who is the man that is standing in front of the crowd?
四、先行詞是人與（動）物：
e.g: Look at the man and his turtle that are walking up the street.
五，先行詞是reason, way（方法），用that代替in which, for which, why，可以省略。
e.g: She admired the way (that) they solved the problem.
巧記口訣：
先行詞是個不定代，the very/only/first; 有高、序，some, all, much, few；指物人，有了which/who。
