Ireally don’t remember how or where I heardthat it takes just three weeks to form a goodhabit.But I do remember I was fascinated(迷住)at the prospect and,at the sametime,doubtful.Still,I decided to try it.There was certain-ly plenty of room in my life for improvement.My dentist had warned me that flossing teeth(用牙线剔牙)was as important as brushing them,and that if Ididn’t begin flossing,my gum(牙床)problems would getworse.I had been meaning to,but had put it off.Okay,I said to myself,I’ll give this three-weekmethod a try.The first day of flossing was the most difficult. Ireally do not remember how or where I heardthat it takes just three weeks to form a goodhabit.But I do remember I was fascinated at the prospect and, at the sametime, doubtful.Still, I decided to try it. There was certain-ly plenty of room in my life for improvement. My dentist had warned me that flossing teeth was as important as brushing them, and that if Ididn’t begin flossing, my gum problems would getworse.I had been meaning to, but had put it off.Okay, I said to myself, I’ll give this three-weekmethod a try. first day of flossing was the most difficult.