Assertion: active grille shutter | /r/CapableOf | improve efficiency
Facets:
value: by opening
type: MANNER
value: to control airflow
type: PURPOSE
value: by closing
type: MANNER
Source sentences:
text: Active grille shutters, which improve efficiency by opening and closing automatically to control airflow, are popping up on a number of new models, including the 2015 Ford Mustang.