( ( ( ( ( ( These cells ) ( ( can not ) ( be ( seen ( without ( ( the help ) ( of ( a microscope ) ) ) ) ) ) ) ) , ) but ) ( they ( are ( ( the ( building blocks ) ) ( of ( our bodies ) ) ) ) ) ) . )
(ROOT (S (S (NP (DT These) (NNS cells)) (VP (MD can) (RB not) (VP (VB be) (VP (VBN seen) (PP (IN without) (NP (NP (DT the) (NN help)) (PP (IN of) (NP (DT a) (NN microscope))))))))) (, ,) (CC but) (S (NP (PRP they)) (VP (VBP are) (NP (NP (DT the) (VBG building) (NNS blocks)) (PP (IN of) (NP (PRP$ our) (NNS bodies)))))) (. .)))
These cells cannot be seen without the help of a microscope, but they are the building blocks of our bodies.
(ROOT (S (NP (NNS Cells)) (VP (VBP are) (NP (NP (DT the) (VBN specialized) (NN building) (NNS blocks)) (PP (IN of) (NP (PRP$ your) (NN body))))) (. .)))