Learn Farsi: این نمایشگر جدید کاملاً ضد خش است. - This new screen is completely scratch-resistant.

zed means anti, counter, or against, and is linked to the noun khash (scratch) using the ezafe (-e). While it is made of a preposition or noun modifying another noun, the whole phrase zed-e khash functions as an adjective here, describing the screen as anti-scratch or scratch-resistant. You can use this exact pattern for many things, such as zed-e âb (waterproof).

What is the grammatical function of the -gar suffix in namâyeshgar?

The suffix -gar attaches to nouns or verb stems to indicate the doer of an action, similar to the -er or -or endings in English. Here it attaches to namâyesh (display or show) to create namâyeshgar, meaning the device that does the displaying: a monitor or screen.

Why doesn't the adverb kâmelan (completely) need an ezafe to connect to the next word?

The ezafe is used to link nouns to their adjectives or to other nouns showing possession. Because kâmelan is an adverb modifying the adjectival phrase zed-e khash, it simply sits next to it without needing an ezafe. The only ezafe markers you need here are between the noun and adjective in namâyeshgar-e jadid and inside the compound zed-e khash.

I remember the -an ending on kâmelan is Arabic. How do we know when to use it versus a native Farsi adverb structure?

The -an suffix (called tanvin) is only ever added to adjectives of Arabic origin, like (complete) becoming . For native Farsi adjectives, you would typically use a phrase like (in a ... way) plus the adjective to form the adverb, though Arabic borrowings like are deeply integrated and completely standard in everyday Farsi speech.