( ( Most amphibians ) ( ( ( ( ( exhibit ( ( external fertilization ) ( of eggs ) ) ) , ) typically ) ( within ( ( ( the water ) , ) ( though ( ( ( some amphibians ) ( such ( as caecilians ) ) ) ( have ( internal fertilization ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (JJS Most) (NNS amphibians)) (VP (VB exhibit) (NP (NP (JJ external) (NN fertilization)) (PP (IN of) (NP (NNS eggs)))) (, ,) (ADVP (RB typically)) (PP (IN within) (NP (NP (DT the) (NN water)) (, ,) (SBAR (IN though) (S (NP (NP (DT some) (NNS amphibians)) (PP (JJ such) (IN as) (NP (NNS caecilians)))) (VP (VBP have) (NP (JJ internal) (NN fertilization)))))))) (. .)))
Most amphibians exhibit external fertilization of eggs, typically within the water, though some amphibians such as caecilians have internal fertilization.
(ROOT (S (NP (NNS Amphibians)) (ADVP (RB sexually)) (VP (VB reproduce) (PP (IN through) (NP (JJ external) (CC or) (JJ internal) (NN fertilization)))) (. .)))