( ( In ( human beings ) ) ( ( ( the ( otoliths ( and ( semi-circular canals ) ) ) ) ( -LRB- ( ( in ( the ( inner ear ) ) ) -RRB- ) ) ) ( ( are ( used ( to ( maintain ( ( balance and ) orientation ) ) ) ) ) . ) ) )
(ROOT (S (PP (IN In) (NP (JJ human) (NNS beings))) (NP (NP (DT the) (NNS otoliths) (CC and) (NN semi-circular) (NNS canals)) (PRN (-LRB- -LRB-) (PP (IN in) (NP (DT the) (JJ inner) (NN ear))) (-RRB- -RRB-))) (VP (VBP are) (VP (VBN used) (S (VP (TO to) (VP (VB maintain) (NP (NN balance) (CC and) (NN orientation))))))) (. .)))
In human beings the otoliths and semi-circular canals (in the inner ear) are used to maintain balance and orientation.
(ROOT (S (NP (DT The) (NNS ears)) (VP (VBP are) (NP (NP (DT an) (JJ external) (NN feature)) (PP (IN in) (NP (JJ human) (NNS beings))) (SBAR (S (VP (VBZ is) (ADJP (JJ responsible) (PP (IN for) (NP (NN balance))))))))) (. .)))