Sentence:  It seems a simple enough matter to extract a general principle of <WSD>subcategorisation</WSD> out of (81), along the lines of:/  (82)      <small>SUBCATEGORISATION PRINCIPLE</small>/  <font color=white>(82)</font>      Any lexical item of category X will be subcategorised with respect/  <font color=white>(82)</font>      to the range of idiosyncratic Complements (i.e. sister constituents)/  <font color=white>(82)</font>      which it permits within the (minimal) X-bar containing it/  The <WSD>subcategorisation</WSD> frame for X will simply be an unordered list of the sets of categories which X permits as its Complements: we assume that the relative ordering of X and its Complements will be determined by independent principles (e.g. the <small>HEAD FIRST PRINCIPLE</small>). 
Meaning of the word marked with <WSD> tags:  The practice of specifying what types of complements a word may take when that word acts as the head of a phrase of a certain category; this specification restricts the wordʼs category, making it smaller, hence a “subcategory” of the wordʼs category.