absent

动词 absent:

1. go away or leave
   同义词：remove

形容词 absent:

1. not in a specified place physically or mentally
2. lost in thought; showing preoccupation
   同义词：absentminded, abstracted, scatty

1. Professor Li is absent, I will take the lesson in the place of him.
   李教授不在，我替他上课。
2. Please tell me the reason why (=for which) you were absent.
   请告诉我你为什么缺席。
3. Many students were absent, notably the monitor.
   许多学生缺席，特别是连班长也没来。
4. Why was it that he was absent?
   他为什么缺席呢？
5. He gave a lame excuse for being absent.
   他找了个站不住脚的理由来解释缺席的原因。
6. How many students are absent today?
   今天有多少学生缺席？