My sister sits in the front of the library.
要区别in the front of the library.和in front of the library,前者是图书馆里面的前面,后者是图书馆的前面(图书馆外面的前面)
My sister sits in the front of the library.
要区别in the front of the library.和in front of the library,前者是图书馆里面的前面,后者是图书馆的前面(图书馆外面的前面)