Learn Turkish: Yarayı hemen temizlemek gerek, yoksa kötüleşecek. - It is necessary to clean the wound immediately, otherwise it will get worse.

While both words can sometimes translate to "or", yoksa is specifically used here to mean "otherwise" or "or else". It introduces the negative consequence (kötüleşecek) that will happen if the required action (temizlemek) doesn't happen.

Why does the sentence use the plain infinitive "temizlemek" before "gerek"?

Using the plain dictionary form temizlemek (to clean) with gerek (necessary) creates a general statement: "It is necessary to clean". If the speaker wanted to specify who needs to do the cleaning, they would use a personal ending, such as temizlememiz gerek (we need to clean).

Why does "yara" (wound) take the "-yı" ending?

The -yı suffix marks the specific direct object (the accusative case). You use it here because the sentence is about cleaning a specific wound ("the wound"). Notice that verbs still take specific direct objects like this even when they are in their infinitive form (temizlemek).

How does the word "kötüleşecek" build the meaning "it will get worse"?

The root word is kötü (bad). Adding the suffix -leş turns this adjective into a verb meaning "to become", making kötüleşmek (to become bad or to get worse). Finally, the -ecek suffix adds the future tense for "it", giving us "it will get worse".