Please, I need more Ts'íts'àsh in my life. I love that movie so much. Can you share more of the language?
Sure! Here's how verbs work in Ts'íts'àsh.
Verbs have three forms: The imperfect, the perfect, and the conditional. The bare form of the verb is the imperfect, and the perfect and conditional each co-occur with suffixes—-(k)sh and -á, respectively. With the tone, though, stem changes can occur. Here's a summary:
kssh "douses" ~ ksshksh "doused" ~ ksshá "would douse"
kòf "warms" ~ kòfsh "warmed" ~ kófá "would warm"
Here you see the difference between words that end in a sibilant and non-sibilant. When the word ends in a sibilant, it gets a -ksh in the perfect (the k breaks up the sibilant sequences); otherwise it just gets -sh. The conditional suffix is always -á, but in kòf the tone shifts from low to high because the o vowel goes from being in a closed syllable to an open syllable.
Here's how the forms change when a verb ends in a single vowel:
táìsí "dances" ~ táìsíksh "danced" ~ táìsshá "would dance"
khìshk'ù "swells" ~ khìshk'úksh "swelled" ~ khìshkf'á "would swell"
párà "cooks" ~ páráksh "cooked" ~ párá "would cook"
A number of things going on here. The first line represents verbs whose roots end in -i; the second, verbs whose roots end in -o or -u; the last, verbs whose roots end in -a. These are the original four vowels of Ts'íts'àsh (remember that modern e is an older sequence of *ai, and some instances of modern o are older sequences of *au). All three root types take the -ksh perfective suffix. When the final vowel is low, it becomes high. For the conditional, -a final are identical, except that the low tone becomes high. The older *ia sequence for -i-final roots becomes modern -shá, with the high vowel (so older táìsíá became táìsshá). Then for -u/o-final roots, the two rounded vowels become f (which is a bilabial voiceless fricative). In the case of khìshk'ù, any time you have an ejective in a cluster, the ejective marking goes to the end, as the whole thing kind of becomes an ejective.
Now, when a word ends in a double vowel, something slightly different happens:
káì "smolders" ~ káíksh "smoldered" ~ káìrá "would smolder"
We see the same perfect, but when there would be a sequence of too many vowels in the conditional, an r is inserted to break things up. (And recall that fricatives can count as vowels!)
Those are the verb forms of Ts'íts'àsh. The bare root is used for both the imperfective and imperative. A couple examples are shown below:
Àshfá ts' páràfò ì àsshì. "Father is talking to the chef."
Àshfá ts' páràfò ì àsshíksh. "Father talked to the chef."
Àshfá ts' páràfò ì àsshìrá. "Father would talk to the chef."
Negation is simply achieved by the negative ùkh at the end of the sentence:
Àshfá ts' páràfò ì àsshì. "Father is talking to the chef."
Àshfá ts' páràfò ì àsshì ùkh. "Father isn't talking to the chef."
If you're wondering about the future, that's accomplished with the imperfect and either some time designation or discussion of the future being the context. An example is shown below:
Àshfá ts' páràfò ì àsshì. "Father is talking to the chef."
Ráìbáp r àshfá ts' páràfò ì àsshì. "Father will talk to the chef tomorrow."
Jessie and I had a lot of fun designing this verb system. We'd done some maximal verb systems recently, so doing something super minimal that would rely on adverbs and auxiliaries to fill things out was quite refreshing.
Thanks for the ask!