Breakdown of the verb form
ᏞᏍᏗ ᏰᏣᎩᎸᏕᏍᏗ
in "The Parable of the Turtle Riders"


ᏞᏍᏗ ᏰᏣᎩᎸᏕᏍᏗ - you all don't ride it!

ᏞᏍᏗ /tlesdi/ - don't! Used to negate commands

ᏰᏣᎩᎸᏕᏍᏗ /yetsakilvdesdi/ - when y'all will ride it (animate object)

    ᏞᏍᏗ ᏰᏣᎩᎸᏕᏍᏗ - y'all don't ride it! (akilvdi)

[yi + ets-akilvd-esdi]

yi- - used with a negation word (ᏞᏍᏗ in the West, ᏤᏍᏗ or ᎮᏍᏗ in NC) to form a negative phrase. Sometimes referred to as the "irrealis prefix", it can be used to form conditional statements and to express doubt or suppositions such as 'if' or 'when'. Ex. ᏱᏣᏚᎵᎭ - If you want it. Can also be used in a question to express "would" or "might". Ex. ᏱᎦᏬᏂᎭᏍ ᏣᎳᎩ? Might he speak Cherokee?

ets- - bound pronoun for 2nd plural subject + animate/living object used with vowel-stem verbs. Some bound pronouns (but not all) have different forms if the object of the verb is animate or living. Since the Turtle is a living, breathing, walking creature, that form is used here.
See also: look for him and Pronouns III - Animate Object Bound Pronouns for more about using them. 

-akilvd- - stem of the verb "to ride". See: ᎠᎩᎸᏗᎭ - riding it, straddling it, sitting astride something

-esdi - future progressive suffix meaning "it will be happening" for whatever verb it's added to. Often used for commands and negative commands.
A fuller translation of this could be "Y'all don't be riding him/her!" or "Y'all don't be getting on him/her!

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