This book makes synchronic studies of texts and diachronic studies of functions in an effort to illustrate the relationship between clauses and their expression forms. The feature of this book is that it firstly examines the core meaning or functions of each form, and then explores its derived explanations. The following issues are involved in this book: the textural functions of aspect marking, the positions of modal adverbs in texts, the explanations and analysis of function words at the end of sentences, the illustration of information structures, the relationship between the subordinate structures and their context, the contribution of the anaphora to the text structures, the prototype of topics and the definition of Chinese topics, the differences and similarities between a topic chain and “Chinese sentences”. Finally, this book provides an exact definition of “Chinese sentences” based on what are discussed above.