( ( ( Thermometers ( measure temperature ) ) ( with ( ( ( ( ( a bulb ) ( of ( liquid mercury ) ) ) ( that ( can expand ) ) ) or ) ( contract ( as ( the temperature ) ) ) ) ) ) ( changes . ) )
(ROOT (S (NP (NP (JJ Thermometers) (NN measure) (NN temperature)) (PP (IN with) (NP (NP (NP (DT a) (NN bulb)) (PP (IN of) (NP (JJ liquid) (NN mercury))) (SBAR (WHNP (WDT that)) (S (VP (MD can) (VP (VB expand)))))) (CC or) (NP (NP (NN contract)) (PP (IN as) (NP (DT the) (NN temperature))))))) (VP (VBZ changes)) (. .)))
Thermometers measure temperature with a bulb of liquid mercury that can expand or contract as the temperature changes.
(ROOT (S (NP (NP (DT The) (NN liquid)) (PP (IN in) (NP (DT a) (NN thermometer)))) (VP (VP (VBZ expands)) (CC or) (VP (VBZ contracts) (S (VP (TO to) (VP (VB respond) (PP (TO to) (NP (NN heat) (CC or) (NN cold)))))))) (. .)))