( ( Weather ( ( conditions and ) precipitation ) ) ( also ( ( must ( be considered ) ) . ) ) )
(ROOT (S (NP (JJ Weather) (NNS conditions) (CC and) (NNS precipitation)) (ADVP (RB also)) (VP (MD must) (VP (VB be) (VP (VBN considered)))) (. .)))
Weather conditions and precipitation also must be considered.
(ROOT (NP (NP (NP (NNP Precipitation)) (ADJP (RB commonly) (JJ occur))) (PRN (-LRB- -LRB-) (PRP s) (-RRB- -RRB-)) (PP (IN along) (NP (DT a) (JJ cold) (NN front))) (. .)))
Precipitation commonly occur(s) along a cold front.