;;; Lexicon this := sg-lexeme & [ ORTH "this", CATEGORY det ]. these := pl-lexeme & [ ORTH "these", CATEGORY det ]. sleep := pl-lexeme & [ ORTH "sleep", CATEGORY vp ]. sleeps := sg-lexeme & [ ORTH "sleeps", CATEGORY vp ]. dog := sg-lexeme & [ ORTH "dog", CATEGORY n ]. dogs := pl-lexeme & [ ORTH "dogs", CATEGORY n ].