( ( Using ( the newspaper ) ) ( , ( ( bar ( graphs ( , ( circle ( graphs ( and ( line graphs ) ) ) ) ) ) ) ( ( are explored ) . ) ) ) )
(ROOT (S (S (VP (VBG Using) (NP (DT the) (NN newspaper)))) (, ,) (NP (NN bar) (NNS graphs) (, ,) (NN circle) (NNS graphs) (CC and) (NN line) (NNS graphs)) (VP (VBP are) (VP (VBN explored))) (. .)))
Using the newspaper, bar graphs, circle graphs and line graphs are  explored.
(ROOT (S (NP (NNP Circle) (NNS graphs)) (VP (VBP are) (ADJP (JJ useful) (PP (IN for) (S (VP (VBG showing) (NP (NP (NNS percents)) (PP (IN of) (NP (DT a) (NN whole))))))))) (. .)))