Аннотация:This article addresses the three factors involved in choosing between overt and null forms. The choice may be lexically controlled or uncontrolled; it may be grammatically determined or undetermined; it may be contextually sensitive or free. Each position of a syntactic structure can be characterised by means of three binary features [±L], [±G], [±C]. In some respects, feature characterisation has an advantage over the familiar approach of identifying a null subject or a null object as one of the four standard empty categories. It provides a mechanism for revealing important differences and similarities between languages and guarding against overgeneralisation and undergeneralisation.
