1.Howmanytimesdidyoubrushyourteethyesterday?·Finding：Af...
问题详情：manytimesdidyoubrushyourteethyesterday?·Finding：Afull33%ofseniorsbrushtheirteethonlyonceaday.·Step：Removethe300typesofbacteriainyourmoutheachmorningwithabattery－operatedtoothbrush.Brushgentlyfo...