Abstracts: Principle of the use of holes for a broad range， it is a mathematical combination of the most basic principle， the application of the principle holes can solve many problems concerning the existence of a combination of In the 20th century， many studies are directed at holes the promotion of the principle， Ramsey theory， in which reached its It is precisely because of the extensive use of pigeon holes principle， and subject to different types of answers to very different methods， so the principle of the structure of holes is also a variety of In this paper， these methods have been collated and summarized to form seven commonly used construction Keywords: pigeonhole principle; structure; pigeons; cage; Category
