Learn Turkish: İyi ki bu yaygın salgın bizi hiç etkilemedi. - Fortunately, this widespread epidemic did not affect us at all.

This suffix (-gIn / -kIn / -gUn / -kUn) attaches to verbs to create adjectives or nouns that describe the result or state of that action. yaygın (widespread) comes from yaymak (to spread). salgın (epidemic) comes from salmak (to release or let loose). Both describe something that has reached a certain state through the action of the root verb.

Wait, salmak means to release or let go. How does that connect to the medical meaning of salgın (epidemic)?

In Turkish, diseases or outbreaks are conceptually thought of as being released or let loose upon a population. Adding the -gın suffix to salmak creates a noun for that released thing—an epidemic or outbreak.

Does İyi ki always take a standard past or present tense verb like etkilemedi, or can it take the conditional?

It takes a standard, factual tense like the past tense seen here. Unlike 'I wish' (keşke), which requires a conditional or subjunctive verb for hypothetical situations, İyi ki (Fortunately / It is a good thing that) states a real, factual outcome.

What is the root of the verb etkilemedi?