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    This is Hong Kong Middle School. It is very big and beautiful. There are 34 classes, 300 teachers and 3, 500 students in the school. In the middle of the school there is a tall building. It's for us to have classes. All the classrooms are there. There are some small rooms, too. They are offices for the teachers to work. All the teachers get ready for their lessons there.

    In front of the tall building, there is a small one. It is the library. There are many books there. The teachers and the students like to read books in it. Sometimes they borrow(借)books from it.

    There is a dining hall behind the tall building. Some of the students have lunch in it.

    I like my new school very much.

下列各项中，属于哺乳动物共同特征的是（  ）

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