Syntactic change can be defined as the change in syntactic structre of a particular language during the passage of time . In this respect , diachronic syntax is considered as a type of comparative syntax , where the comparison takes place between the different stages of the language , old , middle and modern according to English , rather than between different variations of that language during the same period of time .
In this brief introduction to the subject one can look at syntactic change according to two approaches , the first , the external language approach in which language is studied as an entity , and the second which is the internal approach where the individual properties are important . However , following Lightfoot ( 1979-1999) syntactic change and language acquisition are seen to be connected .
In the theortical part of the study , the researcher tries to find out the causality of syntactic change and its types in English and Arabic ,in addition to the relationship between language acquisition and language change. Some examples chosen from different stages of the two languages are provided in the practical part.