English grammar
Past Modals
"I must have lost it" (past deduction), "she could have called" (unrealised possibility), "they might have already left" (past speculation), "it shouldn't have been done" (criticism). In natural speech, "have" almost always contracts to 've, "should've", "could've", "must've", and sounds so close to "of" that even native writers sometimes misspell it as "should of". Past modals are one of the hardest areas for learners, and one of the most common in natural conversation.
should / could / might / may / must + have + past participle
Real Examples from Native Speakers
"Could have been you."
Interrogating James After A Mysterious Incident
How it works
Formula
should / could / might / may / must + have + past participle
This page combines the textbook rule with real-world English: every example is an unscripted clip from a real native speaker. You're hearing how this grammar point sounds in real life, not in a classroom.