Second, a clue may name a class of objects which includes the answer, like bird for COCK.
( Second ( , ( ( a clue ) ( ( may ( name ( ( a class ) ( of ( objects ( which ( ( ( includes ( the answer ) ) , ) ( like ( bird ( for COCK ) ) ) ) ) ) ) ) ) ) . ) ) ) )
(ROOT (S (ADVP (LS Second)) (, ,) (NP (DT a) (NN clue)) (VP (MD may) (VP (VB name) (NP (NP (DT a) (NN class)) (PP (IN of) (NP (NP (NNS objects)) (SBAR (WHNP (WDT which)) (S (VP (VBZ includes) (NP (DT the) (NN answer)) (, ,) (PP (IN like) (NP (NP (NN bird)) (PP (IN for) (NP (NNP COCK))))))))))))) (. .)))
Clues may not be categorical.
( Clues ( ( ( may not ) ( be categorical ) ) . ) )
(ROOT (S (NP (NNS Clues)) (VP (MD may) (RB not) (VP (VB be) (ADJP (JJ categorical)))) (. .)))