( ( ( ( 250 million ) years ) ago ) ( There ( ( was ( ( ( ( ( ( ( just ( one ( giant continent ) ) ) ( on Earth ) ) , ) ( called Pangaea ) ) , ) and ) ( ( ( a ( giant ocean ) ) , ) ( called Panthalassa ) ) ) ) . ) ) )
(ROOT (S (ADVP (NP (QP (CD 250) (CD million)) (NNS years)) (RB ago)) (NP (EX There)) (VP (VBD was) (NP (NP (NP (RB just) (CD one) (JJ giant) (NN continent)) (PP (IN on) (NP (NNP Earth))) (, ,) (VP (VBN called) (NP (NNP Pangaea)))) (, ,) (CC and) (NP (NP (DT a) (JJ giant) (NN ocean)) (, ,) (VP (VBN called) (NP (NNP Panthalassa)))))) (. .)))
250 million years ago There was just one giant continent on Earth, called Pangaea, and a giant ocean, called Panthalassa.
(ROOT (S (NP (NNP Pangaea)) (VP (VBD began) (S (VP (VBG breaking) (ADVP (RB apart)) (ADVP (NP (QP (CD 250) (CD million)) (NNS years)) (RB ago))))) (. .)))