Casualness

　　Since Americans are very casual1, this can sometimes lead to misunderstandings. A teacher who is friendly and informal2 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 forward3 or gets too personal with the teacher, she will put a stop to it immediately.

　　例句：Although close to tears, she tried to make her voice sound casual.

　　她差不多要哭出来了，但她还是尽量让自己说话的声音听上去像是无所谓的样子。

　　2.informal: adj. not formal or official随便的，非正式的

　　例句：Victor is the ideal sort of teacher-direct, friendly and informal.

　　Victor是那种完美的老师--性格直率，和蔼可亲，不摆架子。

　　3.forward: adv. in a manner of behaving too noticeably or confidently过于引人注目地，放肆地

　　例句：Watch your behavior. Don't act too forward.

　　注意行为举止。别太放肆。

　　Exercise: How is teachers' behavior in America different from that in other countries?

　　Clues to the answer：casual, comfortable, not personal