( ( The ( windchill index ) ) ( ( combines ( ( ( ( air temperature ) and ) ( wind speed ) ) ( to ( ( come up ) ( with ( ( a reading ) ( of ( what ( it ( supposedly ( feels ( like outside ) ) ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT The) (JJ windchill) (NN index)) (VP (VBZ combines) (S (NP (NP (NN air) (NN temperature)) (CC and) (NP (NN wind) (NN speed))) (VP (TO to) (VP (VB come) (PRT (RP up)) (PP (IN with) (NP (NP (DT a) (NN reading)) (PP (IN of) (SBAR (WHNP (WP what)) (S (NP (PRP it)) (ADVP (RB supposedly)) (VP (VBZ feels) (PP (IN like) (NN outside)))))))))))) (. .)))
The windchill index combines air temperature and wind speed to come up with a reading of what it supposedly feels like outside.
(ROOT (S (NP (NNP Windchill)) (VP (VBZ describes) (SBAR (WHNP (WP what)) (S (NP (DT the) (NN temperature)) (VP (VBZ feels) (PP (IN like) (SBAR (WHADVP (WRB when)) (S (NP (DT the) (NN wind)) (VP (VBZ is) (VP (VBN taken) (PP (IN into) (NP (NN account)))))))))))) (. .)))