Gerunds (zarf-fiiller or ulaçlar) are verb forms that function as adverbs, modifying verbs, adjectives, or other adverbs. They typically form adverbial clauses indicating time, manner, cause, condition, etc.

Common Gerund Suffixes:

• -ip / -ıp / -up / -üp: ("and", "and then", sequential actions by the same subject)
  Example: Eve gelip yemek yedim. (I came home and (then) ate food.)
• -erek / -arak: ("by -ing", "while -ing", manner or simultaneous action)
  Example: Koşarak geldi. (He/She came by running.)
  Example: Müzik dinleyerek ders çalışır. (He/She studies while listening to music.)
• -ince / -ınca / -unce / -ünce: ("when", "upon -ing", as soon as)
  Example: Eve gelince seni arayacağım. (I will call you when I get home.)
• -ken: ("while", "when", "as" - added to verb stems, aorist, or future tense stems. Does not follow vowel harmony.)
  Example: Ben uyurken o geldi. (He/She came while I was sleeping.) (uyur + ken)
  Example: Çocukken çok oynardım. (When I was a child, I used to play a lot.) (Here, çocuk + ken)
• -meden / -madan: ("without -ing", "before -ing")
  Example: Yemek yemeden dışarı çıkma. (Don't go out without eating food / before eating food.)
• -eli / -alı: ("since -ing", "since the time that...")
  Example: Seni görmeyeli yıllar oldu. (It has been years since I last saw you.)
• -dikçe / -dıkça / -dükçe / -dükçe / -tikçe / -tıkça / -tükçe / -tükçe: ("as long as", "the more... the more...")
  Example: Çalıştıkça öğrenirsin. (The more you work, the more you learn / As long as you work, you learn.)
• -e ... -e / -a ... -a: (Repeated verb stem with -e/-a, means "by repeatedly -ing", "while continuously -ing")
  Example: Koşa koşa geldi. (He/She came running (continuously/fast).)
  Example: Ağlaya ağlaya anlattı. (She told (it) while crying continuously.)

These are some of the most common gerunds. They add rich adverbial meaning to sentences.