Learn Farsi: ای فرمانده، پادشاه من در این نبرد تسلیم نمی‌شود. - O commander, my king will not surrender in this battle.

The word ey is a formal or literary vocative particle, translating closely to "O" in English (as in "O commander"). While in everyday conversation you might just say a person's name or title to get their attention, using ey adds a dramatic, respectful, or epic tone, which fits perfectly with a sentence about kings and battles.

The current lesson mentions the literary suffix -â for calling out to someone. Could we say farmânde'â instead of ey farmânde?

Technically you might see this in highly classical poetry, but in practical B2-level Farsi, no. The -â suffix is heavily restricted to a few established words like khodâyâ (O God) or shâhâ (O King). For most nouns and titles, especially multi-syllable ones like farmânde, you must use ey to form the formal vocative.

The English translation says "will not surrender", but nemishavad is the present tense. Why isn't the future tense used here?

In Farsi, the continuous present tense is very frequently used to express definitive future actions, much like saying "my king is not surrendering" in English. You could use the strict formal future tense here (taslim nakhâhad shod), but nemishavad sounds perfectly natural, resolute, and is extremely common even in formal contexts.

What is the literal breakdown of the word farmânde?

It is a compound noun made of (command or order) and , which comes from , the present stem of (to give). So a is literally a "command-giver".