( ( Whenever ( fat ( drips ( onto ( ( ( ( ( ( a flame ) , ) ( heating element ) ) , ) or ) ( hot coals ) ) ) ) ) ) ( , ( chemicals ( ( called ( ( PAHs ( -LRB- ( ( polycyclic ( aromatic hydrocarbons ) ) -RRB- ) ) ) form ) ) . ) ) ) )
(ROOT (S (SBAR (WHADVP (WRB Whenever)) (S (NP (NN fat)) (VP (VBZ drips) (PP (IN onto) (NP (NP (DT a) (NN flame)) (, ,) (NP (NN heating) (NN element)) (, ,) (CC or) (NP (JJ hot) (NNS coals))))))) (, ,) (NP (NNS chemicals)) (VP (VBD called) (SBAR (S (NP (NP (NNP PAHs)) (PRN (-LRB- -LRB-) (NP (JJ polycyclic) (JJ aromatic) (NNS hydrocarbons)) (-RRB- -RRB-))) (VP (VBP form))))) (. .)))
Whenever fat drips onto a flame, heating element, or hot coals, chemicals called PAHs (polycyclic aromatic hydrocarbons) form.
(ROOT (S (NP (PRP We)) (VP (VBP call) (NP (NP (DT the) (JJ solid) (NN form)) (PP (IN of) (NP (JJ hydrocarbons) (NN coal))))) (. .)))