~とき (when)
grammar53 sentences
The temporal clause marker とき (also ときに, ときは), placed after a verb, adjective, or noun to mean 'when X.' Dictionary-form verb before とき implies the action hasn't completed yet; past-form implies it has — 行くとき ('when going') vs 行ったとき ('when I went'). Combines freely with progressive ~ている (~ているとき, ~ていたとき) for 'while X was happening.'