• Perfect Modals: May/Might Have

• 
• Use the perfect modal form of may/might to show possibility* about actions/events in the past. 

  
  

  Remember! Use may for strong possibilities and might for weak possibilities.
  

  
  

  subject + may/might + have + past participle 

  
  

  -I may have left my coat in the laboratory. 
  

  (This shows there is a strong possibility that this is true. The coat was left in the laboratory.)
  

  
  

  -She might have forgotten about the meeting. 
  

  (This shows there is a weak possibility that this is true. There could be other reasons why she was late for the meeting.)

• I may have left my laptop in the lecture hall.	You may have taken better notes than Sara.
  I might have seen Jamie in the dorm.	Josh might have passed the final exam.

• *Possibility: the chance that something is true or likely

 Source : Alison