serves as a workable primer for the region 's recent history , 
(ROOT (S (VP (VBZ serves) (PP (IN as) (NP (NP (DT a) (JJ workable) (NN primer)) (PP (IN for) (NP (NP (DT the) (NN region) (POS 's)) (JJ recent) (NN history)))))) (, ,)))
(ROOT (S (VP (VBZ ) (PP (IN ) (NP (NP (DT ) (JJ ) (NN )) (PP (IN ) (NP (NP (DT ) (NN ) (POS )) (JJ ) (NN )))))) (, )))