Breakdown of مگر امروز کار نمیکنی؟ چرا، امروز کار میکنم.
امروزemruz
today
چراcherâ
why
کار کردنkâr kardan
to work
مگرmagar
unless / perhaps (used in tags)
Questions & Answers about مگر امروز کار نمیکنی؟ چرا، امروز کار میکنم.
Why is مگر used at the beginning of the first sentence?
The word مگر is a special marker used to show surprise or to ask a negative question where you expect a certain answer. It translates roughly to 'Wait, aren't you...?' or 'Is it true that you aren't...?'. It shows the speaker originally thought you were going to work today.
Doesn't چرا normally mean 'why'? Why does it mean 'yes' here?
You are right that چرا usually means 'why' in Farsi. But there is a very important exception: when someone asks you a negative question (like 'Aren't you working?'), you use چرا to contradict the negative and say 'Yes, actually I am!'. You cannot use the regular word for yes (بله) in this situation.
How exactly is the negative verb نمیکنی built here?
It is from the compound verb کار کردن (to work). To make a present-tense verb negative, you add the negative prefix نـ directly onto the continuous prefix میـ. So, میکنی (you work) becomes نمیکنی (you don't work).
Why aren't the words for 'you' and 'I' included in these sentences?
Farsi is a pronoun-dropping language, which means you can leave out pronouns like تو (you) and من (I) when the context is clear. The verb endings do the job for you: the ـی at the end of نمیکنی means 'you', and the ـم at the end of میکنم means 'I'.