( ( ( The ( ( most common ) type ) ) ( of ( graph ( used ( to ( illustrate ( physical experiments ) ) ) ) ) ) ) ( ( is ( ( the ( line graph ) ) ( that ( shows ( ( the relationship ) ( between ( two ( different variables ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (DT The) (ADJP (RBS most) (JJ common)) (NN type)) (PP (IN of) (NP (NP (NN graph)) (VP (VBN used) (S (VP (TO to) (VP (VB illustrate) (NP (JJ physical) (NNS experiments))))))))) (VP (VBZ is) (NP (NP (DT the) (NN line) (NN graph)) (SBAR (WHNP (WDT that)) (S (VP (VBZ shows) (NP (NP (DT the) (NN relationship)) (PP (IN between) (NP (CD two) (JJ different) (NNS variables))))))))) (. .)))
The most common type of graph used to illustrate physical experiments is the line graph that shows the relationship between two different variables.
(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))))))))) (. .)))