He says, also, that if you're trying to talk to other people, talk to them in a proper tone of voice.

他还说， 如果您想与其他人交谈，请以适当的语调与他们交谈。

If we are to impress it with our preferences, we ourselves must use the proper tone, which we, in turn, must have caught from our own teachers.

如果我们要用我们的偏好给它留下深刻印象，我们自己必须使用适当的语气，而这又必须是从我们自己的老师那里学来的。