Use of Must have
Use of Must have Deduction or inference (a conclusion based on evidence and reasoning: It is used to denote an opinion of an earlier past …
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Use of Must have Deduction or inference (a conclusion based on evidence and reasoning: It is used to denote an opinion of an earlier past …
“May have and might have” are used to express the possibility or chances of work being done in the past.
Might have–20 to 40% guess of something means chances were less to complete the task. “Might have” used for a complete guess or speculation for the past situation.
May have–50 to 60% chances of doing work. It shows more chances to complete the job.
Must have ¬-
It makes sure that action takes place with strong affirmation. It is sure that action definitely happened.