every definite quantity of a commodity

例句：

1. 1. Every day I go to the gym for exercise.
   我每天去健身房锻炼。
2. 2. Every student should study hard.
   每个学生都应该努力学习。
3. 3. Every time I see him, he seems happy.
   每次见到他，他都显得很开心。