This book "supplies a vocabulary of English words and idiomatic phrases 'arranged … according to the ideas which they express'. The thesaurus, continually expanded and updated, has always remained in print, but this reissued first edition shows the impressive breadth of Roget's own knowledge and interests."
This linguistic study is concerned with the role of the emphasizing particle la- (known as lām al-ta'kīd) in the grammatical traditions of Classical Arabic, as well as with the question of the historical relationship connecting this particle to a set of elements in several other Semitic languages showing comparable forms and functions. Although these particles have hitherto seemed to defy a coherent reconstruction, the very complexity of the data to which they attest proves to provide a key to their interpretation. They represent a critical first step in the refining of our understanding of the history of the Semitic sonorant phonemes.