---________does your grandmother watch TV？---Twice a day．A.How longB.How oftenC.How manyD.How well
网友回答
B
解析分析：twice a day(次数+单位时间)，sometimes(often，usually，seldom等)，
every two years都是“频度”概念，提问时用how often．(延伸)如果对次数twice提问，用how many times，如：How many times does your grandmother watch TV every day？