Indefinite past

The indefinite past tense is formed by adding to the verb stem the suffix -GAN, plus the pronominal type of personal suffixes.

With the verb kelmoq, 'to come':

kelganmanI have come
kelgansanYou have come
kelganHe/she/it has come
kelganmizWe have come
kelgansizYou have come
kelganlar / kelganThey have come

If the verb stem ends with -k or -g, a phonetic assimilation rule changes the suffix into -KAN (and if the verb stems ends with -g, this last consonant becomes -k).
In the same way, if the verb stem ends with -q or -g', the suffix is changed into -QAN (and if the verb stems ends with -g', this last consonant becomes -q).
For instance, with the verb tegmoq, 'to touch':

tekkanmanI have touched
tekkansanYou have touched
tekkanHe/she/it has touched
tekkanmizWe have touched
tekkansizYou have touched
tekkanlar / tekkanThey have touched

The negative is formed by adding to the verb stem the suffix -MA, plus the suffix -GAN and then the personal suffix.

kelmaganmanI haven't come
kelmagansanYou haven't come
kelmaganHe/she/it hasn't come
kelmaganmizWe haven't come
kelmagansizYou haven't come
kelmaganlar / kelmaganThey haven't come

The negative may also be formed using the verb stem plus the suffix -GAN (which is the past participle), followed by the negative copula emas and the personal suffix.

kelgan emasmanI haven't come
kelgan emassanYou haven't come
kelgan emasHe/she/it hasn't come
kelgan emasmizWe haven't come
kelgan emassizYou haven't come
kelgan emaslar / emasThey haven't come

Another and more emphatic negative form is using the past participle, -GAN plus the possessive personal suffixes, followed by the negative word yo'q.
That form is more emphatic, as is its positive counterpart, with bor.

kelganim yo'qI haven't come
kelganing yo'qYou haven't come
kelgani yo'qHe/she/it hasn't come
kelganmiz yo'qWe haven't come
kelganingiz yo'qYou haven't come
kelganlari yo'qThey haven't come