( ( Use ( ( your knowledge ) ( of ( how ( ( the ( electrical ( field lines ) ) ) ( should ( appear ( to ( ( aid you ) ( in ( finding ( the ( equipotential lines ) ) ) ) ) ) ) ) ) ) ) ) ) . )
(ROOT (S (VP (VB Use) (NP (NP (PRP$ your) (NN knowledge)) (PP (IN of) (SBAR (WHADVP (WRB how)) (S (NP (DT the) (JJ electrical) (NN field) (NNS lines)) (VP (MD should) (VP (VB appear) (S (VP (TO to) (VP (VB aid) (NP (PRP you)) (PP (IN in) (S (VP (VBG finding) (NP (DT the) (JJ equipotential) (NNS lines))))))))))))))) (. .)))
Use your knowledge of how the electrical field lines should appear to aid you in finding the equipotential lines.
(ROOT (S (SBAR (IN Since) (S (NP (DT the) (JJ electric) (NN field) (NNS lines)) (VP (VBP point) (ADVP (RB radially)) (ADVP (RB away) (PP (IN from) (NP (DT the) (NN charge))))))) (, ,) (NP (PRP they)) (VP (VBP are) (ADJP (JJ perpendicular) (S (VP (TO to) (VP (VB equipotential) (NP (NNS lines))))))) (. .)))