关于定语从句that和which在什么条件下可互换，什么条件下不
that和which在什么条件下可互换，什么条件下不能？
1,在介词后只有which,不用that，如I like the house around which there are plenty of trees; 2,既代人又代物的，用that,不用which; 3,被修饰词前有every,only,any,some,almost,nearly等词时，只用that.