x1 = k1 is able/can do x2 = k2 = d2 (state/event) under conditions x3 = k3
(state/event) in time x4 = d1.
x4 defaults to the natural duration of the event x2 ( |-----|.">ca'o) so that it also means "x1 has enough time to do x2". See ditcu, kakne.