她注意饮食以控制胆固醇水平。
She watches her diet to ___keep her cholesterol ___down.
使用减速带能有效减少居民区的交通事故。
Using speed bumps is effective for ___keeping ___down traffic accidents in residential areas.
政府实施政策以控制通货膨胀。
The government implemented policies to ___keep ___down inflation.