( ( What good ) ( ( are ( cactus spines ) ) ? ) )
(ROOT (SBARQ (WHNP (WDT What) (NN good)) (SQ (VBP are) (NP (NN cactus) (NNS spines))) (. ?)))
What good are cactus spines?
(ROOT (S (NP (NP (DT The) (NNS spines)) (PP (IN of) (NP (DT a) (NN cactus)))) (VP (VBP help) (SBAR (S (NP (PRP it)) (VP (VBP survive) (SBAR (IN because) (S (NP (NNS spines)) (VP (VB protect) (NP (DT the) (NN cactus)) (PP (IN from) (NP (NNS animals)))))))))) (. .)))