Turkish provides some interesting inspiration as to how the verb system of Diinlang might be developed. Turkish is an agglutinative language so what would be a verb phrase in many languages is represented by a single Turkish word composed of multiple suffixes. These suffixes occur in a specific order so a word can easily be deconstructed by someone familiar with the system. For a natlang, Turkish is relatively regular and consistent system.
In “The Logic of Turkish” the author categorizes verbs as being as stem followed by vocal, dialectical, temporal (or temporal-modal) and personal suffixes. Note that a Turkish verb seems to be constructed backwards compared to English, the pronoun coming at the end.
The vocal suffixes allow a Turkish verb to produce a family of related verbs. The four classes of vocal endings are reflexive, reciprocal, causative and passive.
When more than one vocal ending is applied to a verb stem they will be applied in that order.
For example, a reflexive suffix is placed before the passive. Diinlang already uses the prefix “ge-”, effectively creating a related passive form of another verb. The pronoun “se” is used for “self” and I have considered a system where this can be placed between the subject pronoun and verb rather than after the verb. This is just a small step from using “se” as a prefix to create reflexive verbs. The suffixes discussed here produce several classes of verb from a common root.
The dialectical suffixes negate a verb or show potential or impotential. The latter is equivalent of the English verbs “can/ be able”. In Diinlang this is the verb/ auxiliary verb “zhan”.
After the dialectical suffixes we have what in English would be tense, mood and aspect. Tense and aspect in Diinlang are already well developed. Progressive and perfect aspect uses the prefixes “is-” and “ha-” which can be combined as “isha-” as needed. Tense is indicated by the adverbs “gon” and “wen” or the past suffix “-(i)d”. A habitual aspect may also be added.
Verbal moods are something that has not yet had much work in Diinlang. Currently we have the word “zou” which may be used for subjunctive and/or conditional statements. The categories that Turkish uses do prove helpful. As well as simple, we also see subjunctive, conditional, optative and necessitative moods used. Some of these moods can be used in more than one tense. It is likely in Diinlang words that give a grammatical mood will be placed after tense adverbs but before dialectical words. For example “zou zhan VERB” rather than “zhan zou VERB”.
Like Turkish, modifiers for verbs should have a set order. This may be tense, mood, dialectical and aspect (TMDA), which is reverse alphabetical order in English.