学时，又称教时、课时，是学校教育时间的最小计量单位，它是由若干更短小的时段构成的。学时结构就是这些更小时段的相互关系的总和。学时损耗包括显性损耗和隐性损耗两种。显性损耗是指教师迟到、早退、处理偶发事件以及与教学内容无关的说教等时间的损耗；隐性损耗则是由于 Hours, hours, and hours are the smallest units of measurement for school education. It consists of a number of shorter periods. The structure of the school hours is the sum of the relationship between these more hours. Hour loss includes both explicit and recessive losses. Explicit loss refers to the loss of time for teachers to be late, leave early, handle incidents, and have nothing to do with the teaching content; the recessive loss is due to