On Nov.11", most products online in China are usually sold at the (最低的) prices.
When we left, the kids said goodbye to us (礼貌).
The stamp I bought yesterday (花费)me 20 yuan.
It's a good habit to brush your (牙齿) after a meal.
People often fly kites on sunny and (多风)days.
污染如此严重,人人都应该出一份力来制止它.( so…that )