what is it?
The suffix -(y)ken is a converb — a non-finite verb form that functions like an adverbial clause. It attaches to a verb or a nominal and signals that the action or state it describes is happening at the same time as the main clause event. In English it corresponds to «while …» or «when …». The subject of the -ken clause can be the same as the main clause subject or a different one entirely.
when to use it
Simultaneous actions — one event provides the background frame during which the main event occurs. The -ken clause is the background; the main clause is the foreground.
Nominal or adjectival states — -ken can attach directly to a noun, adjective, or postpositional phrase to mean «when (one) was …». This is common for life-stage references: çocukken (when [I/he/she] was a child), öğrenciyken (when [one] was a student).
Different subjects allowed — unlike some Turkish subordinate clauses, the -ken clause does not require subject co-reference. The subject of the -ken clause is simply marked with the nominative and stated explicitly when it differs from the main subject.
Imperfective aspect only — -ken describes an ongoing or habitual state, so it attaches to imperfective bases (aorist -r/-ar/-er, present continuous -iyor), never to a completed-past (-DI) stem.
formation
The suffix is -ken after a consonant-final base, and -yken after a vowel-final base (the y is a glide that prevents vowel hiatus). The suffix does not undergo vowel harmony — it is always -ken, never *-kan or *-kın.
| base | output form | meaning |
|---|---|---|
| gel-ir (aorist) | gelirken | while coming / on the way |
| konuş-ur (aorist) | konuşurken | while speaking |
| uyu-r (aorist) | uyurken | while sleeping |
| gel-iyor (pres. cont.) | geliyorken | while (in the process of) coming |
| çocuk (noun) | çocukken | when (one) was a child |
| öğrenci (noun) | öğrenciyken | when (one) was a student |
The aorist base is the default choice for -ken. Use the present-continuous base (-iyor) only when you need to emphasise that the background action was explicitly in progress at that moment. In most everyday sentences the aorist base is natural and sufficient.
examples in context
common pitfalls
Attaching -ken to the -DI past stem. The -DI suffix marks a completed event, which is incompatible with the simultaneous, ongoing meaning of -ken. Geldiken is not a valid Turkish form. Use the aorist base: gelirken.
Choosing the wrong aspect base. Both gelirken (aorist) and geliyorken (present continuous) are grammatical, but they are not interchangeable. The aorist base is the neutral, general choice. The present-continuous base stresses that the action was explicitly in progress at that exact moment — use it only when that emphasis is needed. Defaulting to -iyorken in all cases sounds unnatural.
Marking the converb-clause subject incorrectly. When the -ken clause has its own subject, that subject takes the nominative case — not the genitive. A common error is to write onun konuşurken by analogy with genitive-marked subjects in other subordinate clauses. The correct form is simply o konuşurken.