Aspect can be marked with the use of an affix, infix, partial or total reduplication, internal flexion, or tone. Languages that lack morphological strategies for the marking of aspect 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 aspect-marking words that have grammaticalized is restricted to immediately before or after the verb. Aspect marking may also overlap with the marking of other grammatical categories, such as person.

Types:

NoA: The language does not have grammatical aspect, or lacks a morphological strategy to express it.

PerifA: Aspect is expressed periphrastically.

PrefA: Aspect is expressed through the use of a special prefix.

SuffA: Aspect is expressed through the use of a special suffix.

IfxA: Aspect is expressed through the use of a special infix or interfix.

CrcfA: Aspect is expressed through the use of a special circumfix.

SyntA: Aspect is expressed through the use of a polyexponential synthetic affix.[1]

TonA: Aspect is expressed through the use of tone.

PartRdpA: Aspect is expressed through the use of partial reduplication.

RdpA: Aspect is expressed through the use of total reduplication.

InflA: Aspect is expressed through the use of internal flexion.[2]

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] The specifics of these affixes should be detailed in the commentary. Such an affix may express both person marking and aspect, for example.

[2] Internal flexion refers solely to morphological alternation in the root, with no affix triggering the change.