( ( If ( ( ( the heat ) ( absorbed ( by ( the surroundings ) ) ) ) ( is positive ) ) ) ( , ( ( ( the reaction ) ( of ( the system ) ) ) ( ( is endothermic ) . ) ) ) )
(ROOT (S (SBAR (IN If) (S (NP (NP (DT the) (NN heat)) (VP (VBN absorbed) (PP (IN by) (NP (DT the) (NNS surroundings))))) (VP (VBZ is) (ADJP (JJ positive))))) (, ,) (NP (NP (DT the) (NN reaction)) (PP (IN of) (NP (DT the) (NN system)))) (VP (VBZ is) (ADJP (JJ endothermic))) (. .)))
If the heat absorbed by the surroundings is positive, the reaction of the system is endothermic.
(ROOT (S (S (VP (VBZ Is) (NP (NP (DT the) (NN heat)) (PP (IN of) (NP (NP (NN reaction)) (PP (IN for) (NP (DT an) (JJ endothermic) (NN reaction)))))))) (VP (VBZ is) (ADJP (JJ positive))) (. .)))