(By Hedvig Skirgård): "This feature is concerned with phonologically bound marking of imperfective and perfective grammatical aspects. These categories could go by the name of punctual and continuous, preterit and progressive, etc. The answer could be 1 even if only one of these is overtly marked, e.g. if the imperfective is marked by an affix and the perfective is marked by an auxiliary. ❡
There are instances where TAM can be expressed by a combination of an affix and auxiliary or particle. For example, some grammarians state that the imperfective aspect is expressed by a certain form on the verbal root and an auxiliary. If this is a productive and obligatory way of expressing imperfective aspect then such a construction triggers 1 for both this feature (GB086) and the feature on aspectual auxiliaries (GB120 and/or GB520). If not all parts of the discontinuous marking are necessary for expressing imperfective aspect, then only consider the marking that is obligatory. ❡
Please take notice that this feature (GB086) and the features on aspectual auxiliaries GB120 and particles GB520 do not cover exactly the same functions. The features on auxiliaries and particles cover more grammatical aspects than just perfective and imperfective. ❡
If this distinction is only available in some TAM-conditions, this counts as well. For example, if there is no aspectual distinction in the past but it only exists in the present, this still triggers a 1."