Some concrete examples were given here to show how the inverted order happens and what functions the inverted order has 十八、反意疑问句(Tag question) Usages of tag question are discussed in this lecture.It is pointed that in addition to the normal tag questions,we should pay much attention to some exceptions in dealing with this kind of question,which were talked about in detail here. 十九、替代(Substitution) Substitution is a grammatical device for avoiding repetition and achieving textual cohesion.There are three kinds of substitution:nominal14 • Some concrete examples were given here to show how the inverted order happens and what functions the inverted order has. 十八、反意疑问句(Tag question) • Usages of tag question are discussed in this lecture. It is pointed that in addition to the normal tag questions, we should pay much attention to some exceptions in dealing with this kind of question, which were talked about in detail here. 十九、替代（Substitution） • Substitution is a grammatical device for avoiding repetition and achieving textual cohesion. There are three kinds of substitution: nominal