New Reverse-Engineered Xitsonga Dictionary (1 Letter)

Result:
['a', 'e', 'i', 'o', 'u']

Definitions:

a = and then s/he; at

e = at; hey, listen

i = it is; here it is

o = e.g. o ta swi pfuketana; o za a ku...; o ndzi tswale hi ndlela; etc.

u = you (do)

Correct outcomes:
['a', 'e', 'i', 'o', 'u']

False positives:

[]

Applicable rules:
1. All Xitsonga words end in a vowel

Explanations:
1. If we only have one letter, it can only end in a vowel, thus being one itself as there's no other.

Success rate:
100%