Learn Farsi: انگار یک جرقه در ترانسفورماتور باعث شد که کل سیستم سوخته باشد. - It seems a spark in the transformer caused the whole system to burn.

We use the past subjunctive because the action of the system burning is a completed event in the past. When using باعث شدن (to cause), you use the present subjunctive for an action that will happen or generally happens, but the past subjunctive for a result that has already been completed.

Does the word انگار affect the choice of the past subjunctive سوخته باشد?

Yes, it reinforces it! انگار (it seems / as if) introduces speculation or deduction. The past subjunctive is frequently used in Farsi to talk about past events that we are deducing or aren't entirely certain about, making سوخته باشد a perfect fit for this speculative context.

Is the conjunction که strictly required after باعث شد?

It is grammatically expected in formal written Farsi to connect the main clause to the subjunctive clause. However, just like the word 'that' in English, که is very frequently dropped in everyday speech.

How exactly is the past subjunctive سوخته باشد formed in this sentence?

It is built by taking the past participle of the verb, which is سوخته from سوختن (to burn), and adding the present subjunctive forms of the verb 'to be' (باشم، باشی، باشد, etc.). Since کل سیستم (the whole system) is a third-person singular subject, we use باشد]}``` 错误! I need to fix the prompt instructions