As you answer this question, please don't tell me "you don't need to know this, it's above your level." I've been studying Russian for 3 years and live in Russia now.
So for most type II verbs, often times the 1st person singular has a different pattern than the rest of the conjugations. For example:
пов'есить -- пов'ешу пов'есишь пов'есит пов'есим пов'есите пов'есят
люб'ить -- люб'лю л'юбишь л'юбит ...
сад'иться -- са'жусь сад'ишься сад'ится ...
Most of the time there's a shift in stress or a consonant change or both. It's rare to find verbs like говорит where the pattern is basic.
But when is there only a shift in stress? When is there only a consonant change? When is there both?
Are there any patterns? Is there a way to look at a class II verb and where it's stressed in the infinitive and say "Oh, so all I need to know is that there's a shift in stress after the 1st person singular?" Or do I have to memorize for each verb what to do?
Here's what I have noticed:
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* Usually verb stems with a б, в, м, н, п have an "л" added in the first person singular, and then if the last syllable of the infinitive is stressed, the stress shifts to the second-to-last syllable. любить and купи́ть are examples. Easy enough, I haven't found any exceptions
* Usually verb stems with a д, г, з, с, т, ст have a consonant change in the first person singular. But some of these verbs have a shift in stress (водить, носить) , some of them don't (сад'иться).
* говорить has no changes after the 1st person singular, подари́ть and смотреть have stress shifts. Why?