Tense marking
Tense can be marked with the use of an affix (including zero-morphemes), infix, partial or total reduplication, internal flexion, or tone. Languages that lack morphological strategies for the marking of tense may rely on the use of independent words instead. Such words can, however, become grammaticalized, in which case they should be considered affixes; characteristically, the position of tense-marking words that have grammaticalized is restricted to immediately before or after the verb. Tense marking may also overlap with the marking of other grammatical categories, such as person. When a language displays more than one strategy, multiple values can be listed. If one strategy is dominant, a slash (/) can separate the values, with the dominant value appearing first; if there is no dominant strategy, they should be listed with an ampersand (&) separating the values.1
Types:
NoT: The language does not have grammatical tense or lacks a morphological strategy to express it.
PerifT: Tense is expressed periphrastically.
PrefT: Tense is expressed through the use of a special prefix.
SuffT: Tense is expressed through the use of a special suffix.
IfxT: Tense is expressed through the use of a special infix or interfix.
CrcfT: Tense is expressed through the use of a special circumfix.
SyntT: Tense is expressed through the use of a polyexponential synthetic affix.2
TonT: Tense is expressed through the use of tone.
PartRdpT: Tense is expressed through the use of partial reduplication.
RdpT: Tense is expressed through the use of total reduplication.
InflT: Tense is expressed through the use of internal flexion.3
1: For example, SuffT & InflT would mean that suffixation and infixation are equally characteristic of tense marking in the given language, whereas SuffT / InflT would indicate that tense is overwhelmingly marked by suffixation, but there is a subset of verbs where it is expressed through infixation. If different parameter values are distributed in a paradigmatic way (e.g. the marking is conditional on which verbal tense is chosen), that should be indicated in the commentary.
2: The specifics of these affixes should be detailed in the commentary. Such an affix may express both person marking and tense, for example.
3: Internal flection (infixation) means marking of the given function exclusively through change of the verbal root. Morphonological changes of the root alongside or triggered by functional affixes do not count as infixation.