The suffix {-lI'} is to be used when there's an ongoing action, proceeding towards a known goal or stopping point. So I wonder.. If there's an ongoing action, taking place during another action, or during a specified time period, then couldn't that ongoing action be "by definition" described by the {-lI'} ? In other words, if we have a {-taHvIS} during which an ongoing action takes place, then couldn't this ongoing action *always* be expressed by the {-lI'} ? With the "stopping point" of the {-lI'} being the end of the action/time period described by the {-taHvIS} ? Examples: The {qaStaHvIS wej rep, romuluS SuvtaH yaS}, could be instead {qaStaHvIS wej rep, romuluS SuvlI' yaS}, with the "known stopping point" being the end of the three-hour period. The {jISeDtaHvIS, QoQ vIQoytaH}, could be also {jISeDtaHvIS QoQ vIQoylI'}, with the "known stopping point" being the end of "my driving". I can't thing of an example like the ones mentioned, where the {-taHvIS} can't be followed by a {-lI'} instead of a {-taH}. Of course, since I'm not sure with regards to all this, I'd love to hear any opinion on the matter. ~ mayqel qunen'oS