( Basically ( , ( ( a ( strong ( gravitational field ) ) ) ( actually ( ( ( slows down ) time ) . ) ) ) ) )
(ROOT (S (ADVP (RB Basically)) (, ,) (NP (DT a) (JJ strong) (JJ gravitational) (NN field)) (ADVP (RB actually)) (VP (VBZ slows) (PRT (RP down)) (NP (NN time))) (. .)))
Basically, a strong gravitational field actually slows down time.
(ROOT (S (NP (JJ Strong) (JJ gravitational) (NNS fields)) (VP (VBP are) (ADJP (JJ capable) (PP (IN of) (S (VP (VBG altering) (NP (NP (DT the) (NN rate)) (PP (IN of) (NP (NN time) (NN passing))))))))) (. .)))