文化篇
Read the text carefully and be prepared to answer the question:
 
Casualness

Since Americans are very casual, this can sometimes lead to misunderstandings.  A teacher who is friendly and informal with her class, for example, might invite them to call her by her first name.  But the teacher is only trying to create a comfortable learning environment; she doesn't really want the students to treat her like they do their other friends.  If a student acts too forward or gets too personal with the teacher, she will put a stop to it immediately.