Subject	wetland
Predicate	act as
Object	natural filters
Modality	Modality Occurrences
Polarity	POSITIVE
Plausibility	0.9718
Neighborhood Sigma	0.9812
Local Sigma	1.0000
Example Sentences	Sentence Occurrences Source wetlands act as natural filters 6 Google Autocomplete, Answers.com Questions the wetlands act as natural filters 1 Google Autocomplete