Choose the more natural-sounding option from the following past modals to complete each sentence: must have, might have, should have, could have.
EXAMPLE: There's no doubt in my mind. He must have trained for this.
GRAMMAR REVIEW: COULD HAVE vs. MUST HAVE
COULD HAVE
Meaning: Something was possible in the past, but it didn't happen (or we don't know if it happened).
Use: To talk about missed opportunities or past possibilities.
Example:
"I could have called you, but I forgot."
→ It was possible, but I didn't do it.
MUST HAVE
Meaning: We are making a strong logical deduction about the past. We're almost sure something happened.
Use: To express a high probability based on evidence.
Example:
"She must have left early."
→ I'm almost certain she left early (based on what I know).
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