Learn Farsi: قلاب را بدون طعمه پرتاب نکنید.

That is because the negative imperative (commands like 'do not do') and the negative present subjunctive share the exact same form for the second person ('you'). Here, partâb nakonid is a formal or plural command meaning 'do not cast', but nakonid is also the identical form you would use in a subjunctive sentence like 'I hope that you do not cast' (omidvâr-am ke partâb nakonid).

Why do we need the word râ right after gholâb (hook)?

The word râ is the definite direct object marker. Because the sentence specifies 'the hook' (a specific hook) rather than just 'a hook', it requires râ to clearly show that it is the direct target of the action.

How do you pronounce the connection between bedun (without) and to'me (bait)?

You need to add the hidden ezafe vowel sound, pronouncing the phrase as bedun-e to'me. The preposition bedun requires this short '-e' sound to link it to the noun that follows, even though it is not written in the Persian script.

I see partâb (throw/cast) before the verb. Why doesn't it change to match the plural 'you' ending?

The verb partâb kardan (to cast) is a compound verb. In Persian compound verbs, only the helper verb (in this case, kardan, conjugated as the negative command nakonid) changes to match the subject or tense. The noun part of the verb, partâb, always stays exactly the same.