单选题Though dentists recommend brushing one’s teeth three times a day, many adult Americans brush just twice a day and floss hardly never.A
brush iust twice a day and floss hardly neverB
brush your teethtwice and never flossC
brush just twice but rarely flo
题目
单选题
Though dentists recommend brushing one’s teeth three times a day, many adult Americans brush just twice a day and floss hardly never.