It is a good habit to brush our teeth t( ) a day

问题描述:

It is a good habit to brush our teeth t( ) a day

twice

你好.填twice.一天刷2次牙是个好习惯。

1.twice= two times
2.前面是个完整的句子,twice a day 是时间状语.
希望对你有帮助.