(S (S (NP (NP (NP (BASENP (DT The) (NNP Large) (NNP Hadron) (NNP Collider)) (PP (IN at) (BASENP (NNP CERN)))) (CC and) (BASENP (DT the) (NNP Tevatron))) (PP (IN in) (BASENP (DT the) (NNP United) (NNPS States)))) (VP (VBP are) (VP (VBG searching) (PP (IN for) (NP (NP (BASENP (DT a) (NN particle)) (PRN (COMMA ,) (BASENP (DT the) (NNP Higgs) (NN boson)) (COMMA ,))) (SBAR (WHNP (WDT that)) (S (VP (MD will) (VP (VB constitute) (NP (BASENP (NN evidence)) (PP (IN for) (BASENP (DT this) (NN theory))))))))))))) (PERIOD .))