Abstract
The purpose of the thesis is to analyze a special structure in the oral conversation. That is, pre-sequences. The focus of our discussion is pre-announcements and pre-requests, and the data is basically Mandarin Chinese. Owing to the fact that pre-sequences have the feature of indirectness, the theoretical structure of indirect speech acts (ISAs) is then used in the discussion of pre-sequences. The purpose is to have a better understanding of the structure of pre-sequences. In addition, because indirectness is closely related to politeness, the Politeness Principle (PP) is also taken into the discussion. The result shows that the indirectness in pre-sequences has a close relationship with the preconditions of executing certain action. The phenomenon is similar with the felicity conditions used in the speech act theory. Besides, the application of the PP is also connected to the numbers of preconditions. The reason is that the necessity of a precondition should be explained by the maxims of the PP.