( Potassium ( , ( ( ( ( as ( ( the ( seventh ( ( most common ) element ) ) ) ( on ( ( the ( Earth 's ) ) surface ) ) ) ) and ) ( in ( the oceans ) ) ) ( , ( ( may ( be ( found ( in ( ( minor quantity ) ( in ( most ( water supplies ) ) ) ) ) ) ) ) . ) ) ) ) )
(ROOT (S (ADVP (RB Potassium)) (, ,) (PP (PP (IN as) (NP (NP (DT the) (JJ seventh) (ADJP (RBS most) (JJ common)) (NN element)) (PP (IN on) (NP (NP (DT the) (NN Earth) (POS 's)) (NN surface))))) (CC and) (PP (IN in) (NP (DT the) (NNS oceans)))) (, ,) (VP (MD may) (VP (VB be) (VP (VBN found) (PP (IN in) (NP (NP (JJ minor) (NN quantity)) (PP (IN in) (NP (JJS most) (NN water) (NNS supplies)))))))) (. .)))
Potassium, as the seventh most common element on the Earth's surface and in the oceans, may be found in minor quantity in most water supplies.
(ROOT (S (NP (NP (JJS Most)) (PP (IN of) (NP (NP (NN earth) (POS 's)) (NN water)))) (VP (VBZ is) (VP (VBN located) (PP (IN in) (NP (NNS oceans)))))))