( ( Crocodiles ( ( do n't ) ( ( sweat . ) ( To ( keep cool ) ) ) ) ) ( , ( they ( ( ( open ( their mouths ) ) ( in ( ( a process ) ( that ( is ( called ( `` ( ( ( ( mouth gaping ) , ) '' ) ( which ( is ( ( a lot ) ( like panting ) ) ) ) ) ) ) ) ) ) ) ) . ) ) ) )
(ROOT (S (S (NP (NNS Crocodiles)) (VP (VBP do) (RB n't) (S (NP (NP (NN sweat)) (. .) (S (VP (TO To) (VP (VB keep) (ADJP (JJ cool))))))))) (, ,) (NP (PRP they)) (VP (VBP open) (NP (PRP$ their) (NNS mouths)) (PP (IN in) (NP (NP (DT a) (NN process)) (SBAR (WHNP (WDT that)) (S (VP (VBZ is) (VP (VBN called) (NP (`` ``) (NP (NN mouth) (NNS gaping)) (, ,) ('' '') (SBAR (WHNP (WDT which)) (S (VP (VBZ is) (NP (NP (DT a) (NN lot)) (PP (IN like) (NP (VBG panting))))))))))))))) (. .)))
Crocodiles don't sweat. To keep cool, they open their mouths in a process that is called "mouth gaping," which is a lot like panting.
(ROOT (S (S (VP (VBG Lying) (PP (IN with) (NP (PRP$ their) (NNS mouths))) (ADVP (RB open)))) (, ,) (NP (DT a) (NN behavior)) (VP (VBD called) (SBAR (S (NP (NNP gaping)) (, ,) (ADVP (RB probably)) (VP (VBZ serves) (NP (NP (DT the) (NN function)) (PP (IN of) (S (VP (VBG cooling) (PRT (RP down)) (PP (IN for) (NP (NNS crocodiles))))))))))) (. .)))