Learn Farsi: اگر یک بیگانه حمله می‌کرد، هیچ‌کس به جز تو ما را نجات نمی‌داد. - If an alien attacked, no one except you would save us.

In Farsi second conditionals (unreal or imagined situations in the present), the "if" clause starting with اگر can use either the simple past or the past continuous. Using the past continuous (حمله می‌کرد) instead of the simple past (حمله کرد) is very common here and simply emphasizes the hypothetical nature of the event.

How does Farsi express the "would" in "would save"?

Farsi doesn't have a separate word for "would". Instead, in these unreal conditional sentences, the result clause uses the past continuous tense to mean "would do" something. The prefix می added to the past stem creates this meaning. So, نجات می‌داد means "would save", and adding the negative نـ gives us نجات نمی‌داد (would not save).

Why is the verb negative (نجات نمی‌داد) when the English translation says "no one ... would save us"?

Farsi requires double negatives! Whenever you use a negative pronoun like هیچ‌کس (no one / nobody), the main verb of that sentence must also be negative. A literal English translation of the Farsi structure would be "No one would not save us."

Why is را attached to ما?