(By Hedvig Skirgård): "This question aims to capture productive paradigms of overt tense marking. ‘Morphological marking on the verb’ means that the marker has to form a phonological unit with the verb. The marking of tense can involve affixes, clitics, suppletion, tonal marking and/or reduplication. This feature aims to capture overt marking of past tense on the verb. Lack of other marking is not enough. There are instances where TAM can be expressed by a combination of an affix and auxiliary or particle. For example some grammarians state that past tense is expressed by a certain aspect on the verbal root and an auxiliary. If this is a productive and obligatory way of expression past tense then this construction triggers 1 for both this feature (GB083) and the feature on tense auxiliaries (GB121). If the marking of past tense is accomplished by more than one marker and at least one is bound, code 1. If not all parts of the discontinuous marking are necessary for expressing past tense, then only consider the marking that is obligatory. ❡
The past tense marker should be dedicated to past tense and not also mark perfective aspect, present, or future. A non-future marker is not enough for a 1 here."