Past and Perfect

Currently in Diinlang the tense of a verb is marked by proceeding it with the words “gon” for future and “wen” for past. Perfect aspect is marked by preceding the verb with “dun”, which is placed after a tense marker if present. Continuous/ Progressive aspect is indicated by the prefix “is-” being added to the verb itself. A similar system is used by a number of other conlangs and in many creole languages.
In many conlangs such markers are called “particles” but it may be more accurate to consider them as adverbs.
My recent attempt at novella writing made me look deeper into the subject of tense. Some novels are written in present tense but the majority are written in past tense, usually simple past, past perfect and past progressive.
Some creoles, such as Hawaiian, have a considerable body of printed material but constantly having to write “wen” (or some other tense marker or auxiliary verb) in each sentence seems inefficient. A good case can be made for having a more compact indicator of a past tense.
Jespersen reached a similar conclusion and selected the suffix “-d” for this purpose. I cannot fault his logic in this choice so propose that past tense in Diinlang can be marked with the suffix “-d”. Most verbs in Diinlang end in “-m”, “-n”, “-ng” or a vowel, so this is phonically compatible. In the rare cases where a word already ends in “d” then “-id” will be used. A word ending in “t” may take either the “-d” or “-id” suffix, as the writer prefers. Pronounciation will be much the same. This system is used in parallel with the use of “wen” as an adverb. In Diinlang one can write the past tense as:
wen VERB”, “VERBd” or “wen VERBd”, although the last is, of course, somewhat redundant.
The “duoverbs” discussed elsewhere use “-t” for their past form. For the moment I will keep this variation, it being more desirable for the past of “riy” (write) to be “riyt” rather than “riyd”. Logically it might be better to use “-t” for all past tense marking.
The progressive aspect of a verb is created using “is-” as a prefix. A past progressive verb may therefore be written as “wen isVERB” or “isVERBd”. It seems logical to drop “dun” as an adverb and revert to the earlier system of having perfect aspect marked with a prefix. Rather than “dun-” I propose to emulate Jespersen by using “ha”, but as the prefix “ha-” rather than as an auxiliary. The perfect progressive can therefore be formed as “isha-”, the perfect passive as “hage-” and the perfect progressive passive as “ishage-”.
Present perfect is “haVERB”.
Past perfect is “wen haVERB” or “haVERBd
This system also gives us a single word form that can be used as an active past participle.