A Polish past tense verb tells you who was speaking. The form is built from a participle that agrees, so a man and a woman saying the same sentence use different endings, and a learner has to make a decision about themselves before the sentence can finish. English requires nothing of the kind, and there is no way to avoid it.
On top of that sits aspect, which is compulsory in the same sentence, so an ordinary remark about yesterday needs two decisions English needs none of, made at once and at speaking speed.
Six patterns, and the one idea underneath four of them
- robić and zrobić, to do, twice. Almost every Polish verb comes as a pair: one for an action in progress or repeated, one for an action completed. Choosing between them is compulsory in every sentence.
- Czytałem and Przeczytałem, I was reading and I read it through. Same past tense, different verb, and the difference is whether the reading finished.
- iść and chodzić, to go on one occasion and to go habitually. Verbs of motion split again on top of the aspect pair, which is why they are taught separately.
- Mam dwa koty and Mam pięć kotów, I have two cats and I have five cats. Numbers from five upward take the genitive plural, so counting changes the noun ending.
- Czy to jest twoje, is this yours. Czy opens a yes or no question and has no English equivalent beyond word order.
- Nie mam czasu, I have no time, the genitive of negation again, this time with an abstract noun.
Two systems meeting in one form
Aspect works as it does across the Slavic languages: verbs come in pairs, one for the process and one for the completed act, the pairing has to be stored because no rule generates it, and there is no neutral third option to reach for. Sometimes a prefix makes the perfective, sometimes the stem changes, and sometimes the two words are unrelated.
The gender agreement is the Polish addition and it is more elaborate than it first looks. In the plural there are two classes rather than three, and they are not two of the three: one set of forms for any group containing a man, another for absolutely everything else. So a sentence about four men and a sentence about four women take different verb forms, different adjective forms and different numerals.
Both systems are conceptually simple and both have to resolve before the word leaves your mouth. That combination, easy to explain and expensive to perform, is the honest shape of Polish grammar.
Defaulting to one aspect and one gender
Here is the stall and it has two halves that reinforce each other. The imperfective is the dictionary form and the one a learner meets first, so it becomes the default and the perfective is produced only when a teacher is listening. The speaker's own gender form becomes automatic, and the other one, which is needed whenever the subject is somebody else, stays computed.
Neither is corrected, because both produce grammatical Polish saying something slightly different or slightly odd. The exit is narrow and deliberate: take twenty things you did yesterday, say each one twice with each aspect and say what changed, and then say each one again as though a woman were speaking and as though a group were. It is dull, it takes a fortnight, and it moves both decisions from computation into habit, which is what a paid hour is well used for, in what a teacher is worth, and what you can do alone.
Same sentence, four forms
Who is speaking, and how many, and what the verb does about it
The same past tense verb takes four different endings depending on facts about the subject that English never marks.
No man involved
- Different from the masculine by one vowel
- The larger of the two plural classes by far
A man involved
- The form most textbooks print as the default
- Different verb, adjective and numeral forms
The bottom right cell is the one that surprises people: one man in a group of twenty women moves the whole sentence into the other class. That is grammar rather than a statement about anything, and it is not negotiable.
Two references for a form with two systems in it
The Wielki slownik jezyka polskiego at wsjp.pl is free, is written by linguists rather than for tourists, and gives the aspect partner along with the grammatical information for any entry. It replaced the bilingual dictionary, which gives one half of an aspect pair and calls it the word, which is how learners end up with decks full of half verbs.
Anki is the other half and the decision is what goes on the card. The item is the pair, both halves on the front, with a phrase rather than a bare verb, and for anything that will appear in the past tense it is worth writing the sentence in the first person so the agreement comes with it. It replaced the vocabulary list with one verb per line, which stores half of the item. Free on desktop and Android, paid once on iOS.
The mistake: learning the genders as three
Polish is described as having three genders everywhere, and counting the categories that actually change an ending gives five: the masculine splits by whether the thing is alive, and the plural splits into groups containing a man and everything else. A learner working from the three-gender description will be surprised by endings that the description does not predict, repeatedly, and will conclude that there are exceptions.
There are not many exceptions. There are five categories, and learning them as five from the beginning costs nothing extra and removes an entire class of confusion. It also makes the numeral rule intelligible rather than arbitrary, since the same split is what makes counting men different from counting anything else, which is set out in what each ending does, and which preposition demands it.
What the verb forms rest on
Both the aspect and the agreement are carried in endings that differ by a syllable or a consonant, and several of those consonants belong to the three sibilant series, so hearing which form was used depends on hearing those apart, in sz, cz, s and c, and the pairs that decide the word. The verbs themselves are built from roots shared across Slavic with prefixes that carry both meaning and aspect, in roots shared across Slavic, and the prefixes that multiply them. And resolving both decisions inside a conversation rather than on paper is choosing a case while the sentence is still moving.