Subject	convex lens
Predicate	be used
Object	to correct farsightedness
Modality	Modality Occurrences
Polarity	POSITIVE
Plausibility	0.8811
Neighborhood Sigma	0.9445
Local Sigma	1.0000
Example Sentences	Sentence Occurrences Source convex lenses are used to correct farsightedness 3 Google Autocomplete