All the built-in adjectives on Basic Inform, from even and odd (for numbers) to symmetric (for relations).
§1. See test case BIP-Adjectives.
Something to watch out for here is that the domain of an adjective with an intentionally broad kind has to be written in a way which considers covariance and contravariance. Thus, "list of values" matches every list, because "list of K" is covariant: but "activity on values" does not match every activity, because "activity on K" is contravariant, and instead "activity on nothing" is needed.
Part Five - Adjectival Definitions Section 1 - Miscellaneous Useful Adjectives Definition: a number is even rather than odd if the remainder after dividing it by 2 is 0. Definition: a number is positive if it is greater than zero. Definition: a number is negative if it is less than zero. Definition: a text is empty rather than non-empty if I6 routine "TEXT_TY_Empty" says so (it contains no characters). Definition: a text is substituted rather than unsubstituted if I6 routine "TEXT_TY_IsSubstituted" says so (any square-bracketed text substitutions in it have been made). Definition: a table name is empty rather than non-empty if the number of filled rows in it is 0. Definition: a table name is full rather than non-full if the number of blank rows in it is 0. Definition: a nothing based rulebook is empty rather than non-empty if I6 routine "RulebookEmpty" says so (it contains no rules, so that following it does nothing and makes no decision). Definition: an activity on nothing is empty rather than non-empty if I6 routine "ActivityEmpty" says so (its before, for and after rulebooks are all empty). Definition: an activity on nothing is going on if I6 routine "TestActivity" says so (one of its three rulebooks is currently being run). Definition: a list of values is empty rather than non-empty if I6 routine "LIST_OF_TY_Empty" says so (it contains no entries). Definition: a use option is active rather than inactive if I6 routine "TestUseOption" says so (it has been requested in the source text). Definition: a verb is modal rather than non-modal if I6 routine "VerbIsModal" says so (it modifies the likelihood of another verb happening, rather than being meaningful itself). Definition: a verb is meaningful rather than meaningless if I6 routine "VerbIsMeaningful" says so (it has a meaning in Inform as a relation, rather than existing only to be printed out).
§2. See test case BIP-RelationAdjectives-G.
Section 2 - Adjectives for Relations Definition: a relation is equivalence if I6 routine "RELATION_TY_EquivalenceAdjective" makes it so (it is an equivalence relation, that is, it relates in groups). Definition: a relation is symmetric if I6 routine "RELATION_TY_SymmetricAdjective" makes it so (it is a symmetric relation, that is, it's always true that X is related to Y if and only if Y is related to X). Definition: a relation is one-to-one if I6 routine "RELATION_TY_OToOAdjective" makes it so (it is a one-to-one relation, that is, any given X can relate to only one Y, and vice versa). Definition: a relation is one-to-various if I6 routine "RELATION_TY_OToVAdjective" makes it so (it is a one-to-various relation, that is, any given Y has only one X such that X relates to Y). Definition: a relation is various-to-one if I6 routine "RELATION_TY_VToOAdjective" makes it so (it is a various-to-one relation, that is, any given X relates to only one Y). Definition: a relation is various-to-various if I6 routine "RELATION_TY_VToVAdjective" makes it so (it is a various-to-various relation, that is, there are no limitations on how many X can relate to a given Y, or vice versa). Definition: a relation is empty rather than non-empty if I6 routine "RELATION_TY_Empty" makes it so (it does not relate any values, that is, R(x,y) is false for all x and y).
§3. See test case BIP-RealAdjectives-G.
Section 3 - Adjectives for Real Numbers (not for Z-machine) Definition: a real number is positive if it is greater than zero. Definition: a real number is negative if it is less than zero. Definition: a real number is infinite rather than finite if it is plus infinity or it is minus infinity. Definition: a real number is nonexistent rather than existent if I6 routine "REAL_NUMBER_TY_Nan" says so (it results from an impossible calculation, like the square root of minus one).
Basic Inform ends here.
§5. ...except that this is not quite true, because like most extensions it then quotes some documentation for Inform to weave into index pages: though here it's more of a polite refusal than a manual, since the entire system documentation is really the description of what was defined in this extension.
---- DOCUMENTATION ---- Unlike other extensions, Basic Inform is compulsorily included with every project. It defines the phrases, kinds and relations which are basic to Inform, and which are described throughout the documentation.