( ( A ( line ( ( graph or ) ogive ) ) ) ( ( ( represents ( change ( over time ) ) ) ( by ( connecting ( points ( ( placed ( on ( specific coordinates ) ) ) ( to ( show fluctuations ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT A) (NN line) (NN graph) (CC or) (NN ogive)) (VP (VBZ represents) (NP (NP (NN change)) (PP (IN over) (NP (NN time)))) (PP (IN by) (S (VP (VBG connecting) (NP (NP (NNS points)) (VP (VBN placed) (PP (IN on) (NP (JJ specific) (NNS coordinates))) (S (VP (TO to) (VP (VB show) (NP (NNS fluctuations))))))))))) (. .)))
A line graph or ogive represents change over time by connecting points placed on specific coordinates to show fluctuations.
(ROOT (S (NP (NNP Line) (NNS graphs)) (VP (VBP are) (ADJP (RB especially) (JJ useful) (PP (IN for) (S (VP (VBG showing) (NP (NNS changes)) (PP (IN over) (NP (NN time)))))))) (. .)))