Learn Farsi: مشت زدن و لگد زدن در این ورزش خطرناک است. - Punching and kicking is dangerous in this sport.

In Farsi, you can use the full infinitive form of a verb (ending in -ن) to act as a noun, just like the "-ing" form (gerund) in English. Here, the compound verbs مشت زدن (to punch) and لگد زدن (to kick) are used as the subject of the sentence, so they translate naturally to "punching" and "kicking".

Since there are two actions happening ("punching" and "kicking"), why does the sentence use the singular "is" (است) instead of the plural "are" (هستند)?

In Farsi, when the subject of a sentence is made up of actions, concepts, or inanimate objects, the verb usually stays in the singular form. Even though there are two actions here connected by و (and), they are treated as an inanimate concept, so we use the singular است.

Both "punching" and "kicking" use the word زدن. Why is that?

زدن literally means "to hit" or "to strike" and is one of the most common "helper" verbs in Farsi. It is used to build many compound verbs. مشت means "fist" and لگد means "kick", so combining them with زدن creates the actions "to strike a fist" (to punch) and "to strike a kick" (to kick).

Could we put در این ورزش at the very beginning of the sentence?

Yes, you can! Farsi word order is quite flexible with prepositional phrases. You could say در این ورزش، مشت زدن و لگد زدن خطرناک است ("In this sport, punching and kicking is dangerous") and it would sound completely natural. Putting it in the middle like our example just slightly emphasizes the actions as the main topic.