(S (S (BASENP (DT This)) (VP (VP (VBD caused) (NP (BASENP (DT a) (NN leak)) (PP (IN of) (BASENP (JJ ultra-cold) (JJ liquid) (NN helium))))) (COMMA ,) (S (VP (VBG resulting) (PP (IN in) (BASENP (JJ severe) (NN damage))))))) (PERIOD .))