Study the information about the 3rd Conditional.
Type 3 Conditionals.
This type expresses imaginary situations in the past. They refer to past situations that did not happen.
If + Past Perfect, would/could/ might + have+ past participle
Kate missed the plane yesterday. If she hadn’t missed the plane, she wouldn’t have been late for meeting yesterday.
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If Mike had called earlier, I would have told him about the party.
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