Learn Farsi: بعید است که زن برای انتقام شوهر خود را مسموم کرده باشد. - It is unlikely that the wife had poisoned her husband for revenge.

The phrase بعید است که (it is unlikely that) triggers the subjunctive because it expresses profound doubt rather than stating a fact. Since the suspected poisoning already happened in the past, we must use the past perfect subjunctive to combine that past timeframe with the doubt expressed in the main clause.

Could we say شوهرش را instead of شوهر خود را for 'her husband'?

Yes, both are grammatically correct. However, using خود (self) emphasizes that it was her own husband. At the B2 level, you will frequently see خود used this way in written Farsi or news reports to clearly refer back to the subject of the sentence and avoid any ambiguity about whose husband it is.

Why does the object marker را come after خود instead of immediately after شوهر?

The direct object marker را must always be placed at the very end of the entire noun phrase it modifies. Because the complete direct object here is the phrase شوهر خود (her own husband), the را anchors to the end of that entire block, not just the core noun.

How does the compound verb structure work in مسموم کرده باشد?

The verb is مسموم کردن (to poison, literally 'to make poisoned'). In Farsi compound verbs, only the light verb (here, کردن) conjugates. To form the past perfect subjunctive, the non-verbal part مسموم stays fixed, while becomes its past participle followed by the present subjunctive of 'to be', which is .