Abstract
In this article, it is argued that there are two kinds of natural developmental sequences in second language (L2) acquisition. The differences between them are discussed in terms of four dichotomic dimensions: monostructural vs multistructural, incomplete vs complete, descriptive vs explanatory, and nonimplicational vs implicational. Following this discussion, the first kind, exemplified by the sequence of the developmental stages of English negation, is contrasted in developmental terms with the second kind, which is typified by the developmental sequence of German word order rules. Each of these sequences is shown to have a different meaning or role in L2 acquisition, on the basis of which it is argued that the advocacy of naturalistic L2 acquisition in the classroom is not warranted.
