Breakdown of شک دارم که آنها سرطان را شکست داده باشند.
آنها
they
راrâ
definite direct object marker
کهke
that (conjunction)
شکست دادنshekast dâdan
to defeat
Questions & Answers about شک دارم که آنها سرطان را شکست داده باشند.
Why is the verb shekast dâde bâshand in the perfect subjunctive instead of the present subjunctive?
The main clause shakk dâram ke (I doubt that) expresses doubt, which triggers the subjunctive mood. Because the action of defeating the cancer is something that would have already happened before the moment of speaking, we must use the perfect subjunctive to express a completed action in a doubtful context.
How exactly is the perfect subjunctive formed for this verb?
The base verb is the compound shekast dâdan (to defeat). To make the perfect subjunctive, you take the past participle shekast dâde and add the present subjunctive forms of budan (to be). For the "they" form, that auxiliary verb is bâshand, giving us shekast dâde bâshand.
Why does saratân (cancer) take the specific object marker râ here?
In Farsi, diseases and abstract concepts are often treated as specific, defined entities when they are the direct object of a sentence. Because "cancer" is the specific enemy being acted upon and defeated here, it requires the direct object marker râ.
Could I leave out the word ke (that) in this sentence?
Yes. Just like in English where you can say "I doubt they have defeated cancer", you can safely drop ke in spoken and informal written Farsi. The subjunctive verb shekast dâde bâshand already clearly signals that this is a dependent clause.