This lesson introduces various ways to say when something happens or will happen, in relation to another event.
When とき is modified by a plain-form predicate it refers to the time that is described by the predicate.
When とき modified by a past-tense verb , it refers to the time when or after the action is/was completed.
A plain form verb followed by the particle と describes an action or situation that invariably results in a second action happening.
とき can be used to say when you want somebody to do something
とき can be used to say a general truth about when a certain action happens. This may be an action that is repeated any number of times.
When とき comes before a past-tense sentence. It describes when that event happened.
The particle と can be used to show that when one event happens, another follows after as a consequence.