( ( Blood pressure ) ( ( is ( measured ( with ( ( an instrument ) ( called ( a ( sphygmomanometer ( or ( pressure gauge ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NN Blood) (NN pressure)) (VP (VBZ is) (VP (VBN measured) (PP (IN with) (NP (NP (DT an) (NN instrument)) (VP (VBN called) (NP (DT a) (NN sphygmomanometer) (CC or) (NN pressure) (NN gauge))))))) (. .)))
Blood pressure is measured with an instrument called a sphygmomanometer or pressure gauge.
(ROOT (S (NP (NNP Sphygmomanometer)) (VP (VBZ is) (VP (VBN used) (S (VP (TO to) (VP (VB measure) (NP (NN blood) (NN pressure))))))) (. .)))