( We ( ( start ( with ( ( ( two ( hydrogen atoms ) ) , ) ( each ( with ( one electron ) ) ) ) ) ) . ) )
(ROOT (S (NP (PRP We)) (VP (VBP start) (PP (IN with) (NP (NP (CD two) (NN hydrogen) (NNS atoms)) (, ,) (NP (NP (DT each)) (PP (IN with) (NP (CD one) (NN electron))))))) (. .)))
We start with two hydrogen atoms, each with one electron.
(ROOT (S (NP (EX There)) (VP (VBP are) (NP (NP (CD one) (NNS electrons)) (PP (IN in) (NP (DT the) (NN hydrogen) (NN atom))))) (. .)))