Ancient Egyptian offers an unparalleled opportunity to study how the phonology and grammar of a language changed over a span of thousands of years. For all but its final stage, however, its wealth of written information comes with the serious deficiency of a writing system that obscures vital phonological and morphological information. Moreover, the writing system itself was first deciphered just short of 200 years ago, and our understanding of it, and of the language it represents, is still being refined.

Partly because of these deficiencies, Egyptian has been interpreted on the basis of a number of differing theoretical models. In the realm of grammar, a model based on that of Egyptian's Semitic relatives dominated until fifty years ago, when it gave way to one based on internal syntactic analysis. That second model, dubbed the “Standard Theory” of Egyptian grammar, has vastly improved our understanding of the language, although in the past two decades it has come under increasing attack for defects of its own.

Amid the continuing struggle to understand the grammar of ancient Egyptian, relatively little attention has been paid to how the language changed over time, except in the realm of phonology. Egyptian phonology is still largely analyzed on the basis of Semitic parallels, but the validity of this approach has also been questioned in recent years. Diachronic studies of Egyptian grammar have focused primarily on the relationship between the verbal systems of Middle and Late Egyptian, which show the greatest degree of historical change.