PRESENT TENSE
In many other languages verb also changes its endings for persons. And even in English we change the ending for he / she / it (I work, he works). The same thing happens with Russian verbs too. But we have different endings for each person. This changing of endings of verbs is called conjugation (спряжение).
Pay attention that we replace the infinitive ending -ть / -ти. There are two types of conjugation. The type of conjugation depends on the ending of a verb in the infinitive form. The 1-st type verbs end in -ать, -ять, -еть or -ти in infinitive form.
The 2-d type verbs end in -ить and also some irregular verbs.
Спряжение 1
думать – to think
я думаю
Ты думаешь
Он думает
Мы думаем
Вы думаете
Они думают
Спряжение 2
говорить – to speak
Я говорю
Ты говоришь
Он говорит
Мы говорим
Вы говорите
Они говорят
What also very important to mention is that after 8 letters (к, г, ш, ж, щ, ч, х, ц) we don’t write the ending -ю /-ют / -ят. We use the endings -у / -ут /-ат instead.
Example
- Я пишу, они пишут – I write, they write (not пишЮ, пишЮт)
- Они лежат – they lay (not они лежЯт)