( Asteroids ( ( have ( hit ( ( the Earth ) ( in ( the past ) ) ) ) ) . ) )
(ROOT (S (NP (NNS Asteroids)) (VP (VBP have) (VP (VBN hit) (NP (NP (DT the) (NN Earth)) (PP (IN in) (NP (DT the) (NN past)))))) (. .)))
Asteroids have hit the Earth in the past.
(ROOT (S (PP (IN In) (NP (DT the) (NN past))) (, ,) (NP (NP (NNS asteroids)) (VP (VBG colliding) (PP (IN with) (NP (NN planet) (NN earth))))) (VP (VBZ has) (VP (VBN caused) (NP (JJ many) (NNS organisms)) (S (VP (TO to) (VP (VB die) (PRT (RP off))))))) (. .)))