( If ( we ( recall ( that ( ( work done ) ( ( ( is ( ( a force ) ( times ( a distance ) ) ) ) then ) ( we ( can ( see ( that ( ( ( ( ( multiplying ( ( the force ) ( of gravity ) ) ) , ) above ) , ) ( by ( a distance ) ) ) ) ) ) ) ) ) ) ) ) )
(ROOT (SBAR (IN If) (S (NP (PRP we)) (VP (VBP recall) (SBAR (IN that) (S (NP (NP (NN work)) (VP (VBN done))) (VP (VBZ is) (NP (NP (DT a) (NN force)) (PP (CC times) (NP (DT a) (NN distance)))) (ADVP (RB then)) (SBAR (S (NP (PRP we)) (VP (MD can) (VP (VB see) (S (NP (DT that)) (VP (VBG multiplying) (NP (NP (DT the) (NN force)) (PP (IN of) (NP (NN gravity)))) (, ,) (ADVP (RB above)) (, ,) (PP (IN by) (NP (DT a) (NN distance))))))))))))))))
If we recall that work done is a force times a distance then we can see that multiplying the force of gravity, above, by a distance
(ROOT (S (NP (NNP Force) (NNS times) (NN distance)) (VP (VBZ is) (NP (NP (DT the) (NN equation)) (PP (IN for) (NP (NN work))))) (. .)))