İçin = for + noun / to + verb / for + verb-ing
●It refers always the reason of doing something.
●It always comes after the noun/verb which is used with it.
●To use it with a verb, you should get the noun form of verb by adding "-dık/dik/duk/dük + possesion suffixes" to the root of this verb. And don't forget that "k --> ğ" if the letter coming after "k" is a vowel. It is used when we talk about past actions. Or we can use infinitive form as well.
●Two examples with a verb:
-Geldiğin için teşekkür ederim. = Thank you for coming/because of your coming. (literally: your coming, gel (root) + dik (getting noun form suffix) + in (your, possesion)
{ k --> ğ }
-Gelmek için ne yaptın? = What did you do to come?
●An example with a noun:
-Sadece bir yumurta için markete gitti. = He/she went to market just for an egg.
I hope this text is helpful :)