The essential goal of this project is to set up some clear criterion for the textbook editors, language teachers, and evaluators (or testing designers) to get the knowledge of the levels of learning difficulty in terms of composite sentences reflected in the textbooks. There is in the Curriculum Guidelines of 12-Year Basic Education a clear requirement for the integration of composite sentences and meaning in teaching and learning. However, no clear indicators as to which sentence patterns and how to decode the meanings of those composite sentences has ever been transparent thus far. It is therefore one of the aims to bridge the gap between what is required in the Guidelines and what is short of for the present textbooks. Apparent is the consequence of this project in that it would provide textbooks editors, teachers, and evaluators with concrete principles or references for what can be done with the composite sentences.