im so confused, why do some ir verbs use

[lofty compass]

if anyone could help id greatly appreciate it, ty!

i think i figured it out, the t, v, and m at the end before the conjugation ones conjugate without the iss and the ones without the t, v, and m have the iss

[signal pewter]

It's not this simple: ultimately you have to remember how each -ir verb conjugates

The vast majority of -ir verbs follow the pattern of finir, while those that follow that of partir/dormir etc. are much fewer and considered irregular for that