( ( Tornadoes Tornadoes ) ( ( ( ( ( are ( ( most common ) ( during ( ( the period ) ( of ( spring ( and ( early summer ) ) ) ) ) ) ) ) , ) but ) ( can ( occur ( in ( ( any month ) ( of ( the year ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNP Tornadoes) (NNP Tornadoes)) (VP (VP (VBP are) (ADJP (ADJP (RBS most) (JJ common)) (PP (IN during) (NP (NP (DT the) (NN period)) (PP (IN of) (NP (NN spring) (CC and) (JJ early) (NN summer))))))) (, ,) (CC but) (VP (MD can) (VP (VB occur) (PP (IN in) (NP (NP (DT any) (NN month)) (PP (IN of) (NP (DT the) (NN year)))))))) (. .)))
Tornadoes Tornadoes are most common during the period of spring and early summer, but can occur in any month of the year.
(ROOT (S (NP (NNS Tornadoes)) (VP (MD can) (VP (VB occur) (PP (IN in) (NP (DT any))))) (. .)))