Tourist Information offices can be very helpful.
( ( Tourist ( Information offices ) ) ( ( can ( be ( very helpful ) ) ) . ) )
(ROOT (S (NP (NNP Tourist) (NNP Information) (NNS offices)) (VP (MD can) (VP (VB be) (ADJP (RB very) (JJ helpful)))) (. .)))
Some Tourist Information offices are very unhelpful.
( ( Some ( Tourist ( Information offices ) ) ) ( ( are ( very unhelpful ) ) . ) )
(ROOT (S (NP (DT Some) (NNP Tourist) (NNP Information) (NNS offices)) (VP (VBP are) (ADJP (RB very) (JJ unhelpful))) (. .)))