Subject	radioactivity
Predicate	be used
Object	to determine the age of rocks
Modality	Modality Occurrences
Polarity	POSITIVE
Plausibility	0.7889
Neighborhood Sigma	0.8093
Local Sigma	1.0000
Example Sentences	Sentence Occurrences Source radioactivity is used to determine the age of rocks 1 Google Autocomplete