Type 2 (Unreal Present Conditions): Structure: Simple past (if-clause) + would(n't)/could(n't) + infinitive (= conditional form) (main clause)
Type 3 (Unreal Past Conditions): Structure: Past perfect (if-clause) + would(n't)/could(n't) + have + past participle (= conditional perfect) (main clause)
Mixed Conditional 1 (Type 3 → Type 2): Structure: Past perfect (if-clause) + would(n't)/could(n't) + infinitive (= conditional form) (main clause)
Mixed Conditional 2 (Type 2 → Type 3): Structure: Simple past (if-clause) + would(n't)/could(n't) + have + past participle (= conditional perfect) (main clause)