How do I form the past of verbs like идти or мочь?

They skip the clean -л in the masculine. Идти becomes шёл, шла, шло, шли; мочь becomes мог, могла, могло, могли. Learn these as a short list of exceptions.

The Russian Past Tense: One Stem, Three Gender Endings

Q: Why does быть become была with the stress on the end?

A small group of very common one-syllable verbs — был, жил, брал, пил, дал — throw the stress onto the feminine ending: была, жила, брала. The masculine, neuter and plural keep the stress on the root.

Q: Does aspect change the past tense?

The endings stay the same, but the verb changes. Imperfective я делал means I was doing or used to do; perfective я сделал means I got it done.

Here is the good news I give every beginner who has been dreading Russian verbs: the past tense forgets about person completely. English makes you track "I read, he reads." Russian does the opposite in the past — it stops caring whether you mean I, you or they, and asks one question instead: who or what is the subject, and is it masculine, feminine, neuter or plural? Chop -ть off the infinitive, add one of four endings, and you are done. Читать (to read) gives чита́л, чита́ла, чита́ло, чита́ли. That is the whole engine.

Four endings, one stem

Take the infinitive, drop the -ть, and hang the ending on the stem that's left. The choice depends on the subject:

Subject	Ending	читать → read
masculine (он, я/ты male)	-л	чита́л
feminine (она, я/ты female)	-ла	чита́ла
neuter (оно)	-ло	чита́ло
plural (мы, вы, они)	-ли	чита́ли

Notice what's missing: there is no separate form for "I" versus "he." Он рабо́тал and я рабо́тал use the same word. The verb is reading the subject's gender, nothing else.

This is why "I knew" has two spellings

Because the ending tracks gender, the same first-person sentence looks different depending on who is speaking. A man says я знал; a woman says я зна́ла. Both are "I knew." When you write about yourself in Russian, you are quietly announcing your gender every time you use a past-tense verb — something English speakers almost never think about. Get this one wrong and it doesn't muddle the meaning, but it marks you instantly as a learner, so it's worth locking in early.

Quick self-test: a woman telling you she lived in Moscow says я жила́ в Москве́, not я жил. If you reached for жил, you were agreeing with the wrong gender.

The stress trap: была́, жила́, брала́

Most verbs keep their stress in the same place across all four forms. A small but very common group does not. With a handful of short, high-frequency verbs, the feminine form throws its stress onto the final -а́, while the masculine, neuter and plural keep it on the root. The classic set to memorise: быть → был, была́, бы́ло, бы́ли; жить → жил, жила́, жи́ло, жи́ли; брать → брал, брала́, бра́ло, бра́ли. The same shift hits пить (пила́), дать (дала́) and звать (звала́). It feels fussy, but these are words you'll say daily, so the pattern pays for itself fast.

The verbs that skip the -л

A few verbs refuse the tidy -л ending in the masculine, usually because their stem ends in an awkward consonant. You just have to know them:

Infinitive	Masc.	Fem. / Neut. / Plural
идти́ (to go, on foot)	шёл	шла, шло, шли
мочь (to be able)	мог	могла́, могло́, могли́
нести́ (to carry)	нёс	несла́, несло́, несли́

Идти is the wild one — шёл looks nothing like its infinitive, a leftover from an older root. There are only a dozen or so of these across the whole language, so treat them as vocabulary rather than a rule to derive.

One thing the endings don't tell you: aspect

The four endings are the easy half. The half that actually takes practice is choosing the right verb before you conjugate it. Я де́лал (imperfective) means "I was doing / I used to do"; я сде́лал (perfective) means "I did it, finished." Same endings, different verb, different picture of the action. That choice is a whole skill of its own, which is why it lives in its own guide — see Russian verb aspect once the endings here feel automatic.

Questions people actually ask

Does the Russian past tense change for I, you and he? No. It agrees with the subject's gender and number, not the person. Я знал (a man), я зна́ла (a woman) — both "I knew."

Why does быть become была́ with the stress on the end? A small set of one-syllable verbs — был, жил, брал, пил, дал — shifts the stress to the feminine ending. The other three forms keep it on the root.

How do I form the past of идти or мочь? They skip the clean -л: идти → шёл, шла, шло, шли; мочь → мог, могла́, могло́, могли́. Short list, learn it by heart.

Does aspect change the past tense? The endings don't change, but the verb does — imperfective делал for the process, perfective сделал for the result.

Pick five verbs you already know and say all four past forms out loud, paying attention to where the stress lands. If you want the endings drilled with audio and correction rather than a table you'll forget by Thursday, that's exactly what we're building — see what's coming and get a launch update.

PS — the very first past-tense verb most learners meet is был, "was." Learn был / была́ / бы́ло / бы́ли today and you've already covered the single most useful one.