1. Introduction

This article introduces the evolution of English word class classification from the 18th to the 19th century, from the study of "verbal components" from ancient Greek grammar to universal grammar, to the word class classification of Western Chinese grammarians in the 17th century. The article selected 10 representative English grammar works and analyzed the overall clues and methods of English grammarians in word class classification. Including works such as Alquin's "Grammar Techniques" from York, Ridley's "Grammar Fundamentals", Broca's "Concise English Grammar", as well as innovations in word class classification by Johnson, Wilkins, Harris, and others. At the same time, it is pointed out that the publishing boom of English grammar books in 18th century Britain and 19th century America demonstrated the rich diversity and historical development of English word classes.

2. Classification of word classes in 18th century English

The cycle of word class classification in 18th century English mainly involved the classification methods of three scholars. In his 1700 book "The Key to Knowledge and Skill," Ryan first separated English adjectives into categories and proposed a "four categories and seven types" word class system, including entity words, adjectives, verbs, and auxiliary words, which were further divided into adverbs, prepositions, and conjunctions. Ryan also believes that interjections are a special class of words, but not appropriate words. Priestley proposed the "Octopation" in his 1761 book "Foundations of English Grammar", which classified pronouns independently but did not separate articles. In his 1762 essay "A Brief Introduction to English Grammar," Roth proposed the "nine point system" that is closest to modern English word classes, which classifies articles independently. Murray adopted Roth's nine point system in his 1795 English Grammar and it was widely used in English and American schools in the early 19th century. The classification methods of these three scholars jointly promoted the development and improvement of the English word class system in the 18th century.

3. Classification of word classes in 19th century English

The cycle of word class classification in 19th century English is presented in papers through the classification methods of multiple scholars. Clark and Greene both use the octet to divide words into nouns, pronouns, adjectives, verbs, adverbs, prepositions, conjunctions, and interjections. However, Clark lacks articles, while Greene considers articles and numerals as subcategories of adjectives. Brown proposed the perfect method in 1851, restoring the independent status of participles and following the tradition of Greek Latin compared to Loth's nine part method. Reed, Kellogg, and Nasfield continued to use the octet, but Nasfield emphasized that word class classification should be based on usage intention, believing that the same word may belong to different word classes in different contexts.

4. The cycle of English word class classification

This article provides a detailed exploration of the evolution of word class classification in English from the 18th to the 19th century, including five main aspects: Ryan's first independent classification of English adjectives, Priestley's eight point method becoming mainstream, Roth's nine point method laying the foundation for the modern English word class system, Clark and Greene's and Brown's repeated adjustments to word class classification, and Sweet's regression of four categories and seven classification methods. In addition, the chapter also compares the process of part of speech recognition in ancient Greek and Latin, pointing out that over the past 330 years from the second half of the 16th century to the first half of the 20th century, the classification of English parts of speech has undergone multiple iterations, reflecting the subjective design of researchers.

5. Conclusion

Emphasis was placed on the importance of understanding the classification of English word classes through historical tracing, pointing out that the number of word classes is relatively fixed while the classification method is variable. The standards for evaluating word class systems have been proposed, including teaching, analysis, machine recognition, and logicality, and it is advocated that there should be diverse word class systems to choose from in the academic ecosystem.