( ( ( Flat tires ) ( from ( cactus spines ) ) ) ( ( ( wo n't ) ( be ( a problem ) ) ) . ) )
(ROOT (S (NP (NP (JJ Flat) (NNS tires)) (PP (IN from) (NP (NN cactus) (NNS spines)))) (VP (MD wo) (RB n't) (VP (VB be) (NP (DT a) (NN problem)))) (. .)))
Flat tires from cactus spines won't be a problem.
(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)))))))))) (. .)))