1.1 The infinitive is the name form of the verb, by which it is referred to and listed in the dictionary. But it does not always allow us to predict how the verb is conjugated. Znać (know), stać (stand) and brać (take) are similar infinitives, but "know" is 1st-conjugation (znam, znasz, zna), "stand" is 2nd-conjugation (stoję, stoisz, stoi), and "take" is 3rd-conjugation (biorę, bierzesz, bierze). Infinitives in -eć can also be unpredictable: widzieć (see) is 2nd-conjugation (widzę, widzisz, widzi), while chcieć (want) is 3rd-conjugation (chcę, chcesz, chce). So besides the infinitive form of the verb it is necessary to know also some of its present-tense forms. The 1sg. form is good to know, because -am allows us to predict the 1st-conjugation endings -asz, -a, -amy, -acie, -ają. But the 1sg. form stoję (I'm standing), which is 2nd-conjugation, is similar to the 1sg. form żyję (I'm alive), which is 3rd-conjugation, so one needs to know also the 2sg. forms: stoisz and żyjesz.
The relationship between the infinitive and the present-tense forms of a verb is sometimes totally unpredictable. For jadę, jedziesz, jedzie (go [by vehicle]) the infinitive is jechać. For the infinitive wziąć (take) the present-tense forms show the stem wezm- (wezmę, weźmiesz, weźmie, weźmiemy, weźmiecie, wezmą).

2.1 Knowing and knowing how. Polish has two verbs for "know". Znać is "know, be acquainted with" and is used with persons, places, and most other direct objects. Thus Znam Marysię, Znam Kraków, Znam język angielski (English), and Znam twój adres. Wiedzieć, on the other hand, means "know, be aware of" and is used with object clauses, e.g., Wiem, gdzie ty mieszkasz (I know where you live), with prepositional phrases, e.g., Wiem o tym (I know about that), and with a limited range of pronominal objects, as in Co pan wie o niej? (What do you know about her?), Nic nie wiesz (You don't know anything), and Mama wie wszystko ( Mom knows everything).

2.11 Wiedzieć and umieć are two of a small handful of Polish verbs which have a 1sg. form ending in -em (rozumiem [I understand] is a third). These verbs may be assigned to a FOURTH CONJUGATION. They pose a problem for certain speakers of nonstandard Polish, namely, those who pronounce widzę (I see) and chcę (I want) as "wi-dzem" and "chcem". For these speakers 4th-conjugation verbs have fallen together with 2nd- and 3rd-conjugation verbs, as least for the first-person singular form. To keep the two separate, the learner is advised to pronounce widzę and chcę as "wi-dze" and "chce" and to pronounce wiem, umiem, and rozumiem with a distinct final -m, avoiding hypercorrect pronunciations like "wię", "u-mię", and "ro-zu-mię".

2.2 Being able to and having to. Knowing how is different from being able. Nie mogę dzisiaj pływać means "I can't swim today" (for one reason or other), it doesn't mean I don't know how (nie umiem). (In English we use can in both meanings, both in I can (= mogę) help you and in I can (= umiem) speak Polish.) Mogę means being physically or otherwise able to do something, as well as having permission, e.g., Czy mogę zobaczyć list? (May I see the letter?). It may also have the meaning of likelihood or probability, as in Ania może nie przyjść (Ann may not come, i.e., it's possible she won't come--not to be confused with Ania nie może przyjść (Ann can't come [doesn't have time, isn't allowed to, etc.]).

3. Verbal aspect. Verbs in Polish have a grammatical property called ASPECT: they either have PERFECTIVE aspect or they have IMPERFECTIVE aspect. Perfective verbs present the action in terms of a single completion. For example, when we say Proszę powtórzyć zdanie (Please repeat the sentence) we have in mind a single complete repetition of the sentence. Imperfective verbs, on the other hand, denote actions which are in progress, e.g., Piszę list do babci (I'm writing a letter to Grandma), which are repeated, e.g., Biorę autobus na uniwersytet (I take the bus to the university), or which are timelessly valid, e.g., Mam siostrę (I have a sister). Powtórzyć is a perfective verb, while pisać, brać, mieć, and almost all the other verbs we have had so far are imperfective. With the verb for "write" which we have had so far we can express "I'm writing a letter" (right now) and "I write letters" (often), but we cannot say "I want to write a letter" (i.e., get it written). For that we need the perfective counterpart of pisać, which is napisać. Similarly, we can express "Please repeat that", requesting a single completed repetition, but we cannot say "You are repeating what you said earlier", which calls for the imperfective counterpart of powtórzyć, which is powtarzać.

3.1 Aspect pairs. For most verbal actions Polish has a pair of verbs, a perfective verb which presents it in terms of a single completion and an imperfective verb which presents it as being in progress or repeated. A perfective verb is related to its imperfective counterpart in one of three ways.

3.11 In a few cases the two are entirely different verbs. Imperfective "see", i.e., the process of perceiving something or having the ability to see, is widzieć. Perfective "see", denoting a single complete act of seeing something, catching sight of it, is zobaczyć. Imperfective "take", referring to in-progress or repeated taking, such as taking a daily newspaper, is brać. Perfective "take", denoting a single act of taking something (e.g., "Will you take your bicycle this evening?") is wziąć. Imperfective "talk, say" is mówić, but perfective "say", in the sense of getting something said, making a complete utterance, is powiedzieć.

3.12 In many cases the perfective verb has a prefix which has no other function than to make it perfective. For "write" the prefix is na-, so whereas impfv. pisać denotes the general activity of writing, pfv. napisać means "get something written". For "read" the prefix is prze-, so pfv. przeczytać means "read something through" or "get something read". Many verbs use po- to form their perfective counterpart; they include pfv. pojechać (go somewhere [by vehicle]) and pfv. poprosić (make a request). A convenient way of recording such verb pairs is (na)pisać, (prze)czytać, (po)jechać, (po)prosić, etc., which tells us to use the prefix for perfective aspect and omit it for imperfective aspect.

3.121 Using a prefix with a verb makes it perfective but it does not affect its conjugation. Thus pfv. napisać is conjugated the same as impfv. pisać and pfv. poprosić the same as impfv. prosić.

3.13 The third way that perfective and imperfective verbs are related is that both verbs have a prefix, which is important for the meaning, but the imperfecive verb belongs to a different conjugation class. For example, pfv. powtórzyć is a 2nd-conjugation verb (powtórzę, powtórzysz, etc.), while its imperfective pair is powtarzać, which is a 1st-conjugation verb (powtarzam, powtarzasz, etc.). The derivation of prefixed imperfectives from prefixed perfectives is discussed in Chapter 13.

4. Future tense. Perfective verbs, since they specify completion of the action, cannot denote an action in progress at the moment of speech, because an action cannot be completed at the moment of speech if at the moment of speech it is in progress. For this reason the conjugated forms of a perfective verb are understood as referring to actions expected to be completed in the future. In other words, the present-tense forms of perfective verbs have future meaning. Napiszę list means "I will write a letter"; Przeczytam książkę means "I will read the book"; Pojadę do Nowego Jorku means "I will go to New York"; Poproszę tatę o pieniądze means "I will ask Dad for money"; Zobaczę Marysię dziś wieczorem means "I will see Mary this evening"; Wezmę autobus do miasta means "I will take the bus to town"; Powiem prawdę means "I will tell the truth"; Powtórzę zdanie means "I will repeat the sentence"; and so on.

4.2 The future tense of "be". Być (be) expresses future states with the following forms:

5. The future imperfective. As noted above, the future-tense auxiliary verb forms just given may be combined with an imperfective infinitive (NOT with a perfective infinitive) to refer to future actions that are open-ended, e.g., Będziemy mówić po polsku (We will speak Polish), Gdzie będziecie mieszkać? (Where will you live?). In this construction the infinitive is acceptable in most cases, but the l-form is more commonly used.

6. The l-form. The l-form is a participle (verbal adjective). Used in the predicate of a sentence, it agrees with the subject of that sentence in gender and number. In a future imperfective predicate consisting of the future auxiliary verb and the l-form, the verb agrees with the subject for person and number while the l-form agrees with it for gender and number. The following combinations of "will" and "talk" occur:

6.1 Forming the l-form. The l-form is built on the stem of the infinitive, i.e., the infinitive form minus -ć (this does not apply to infinitives ending in -c; see below). Where the infinitive stem differs from the present-tense stem, as in mieć ~ mam, masz and stać ~ stoję, stoisz, choose the infinitive stem (mie-, sta-). To the stem of the infinitive add -ł- and the gender/number endings. These are the same as for on, namely: masculine -Ø, feminine -a, neuter -o, male-personal -i, and other than male-personal -y. Before -i, hard -ł- softens to -l-.

6.11 When the infinite stem ends in -e-, it shifts to -a- before hard -ł-. For example, widzieć (see) has -e before the soft -ć of the infinitive and before the soft -li of the male-personal form widzieli. But before the hard -ł- of the remaining forms we find -a-: widział, widziała, widziało, widziały.

6.12 When no vowel separates the verb root from the infinitive suffix, as in móc (be able, can) and biec (run), no vowel separates the root from the -ł- suffix either: mógł ("muk"), mogła, mogło, mogli, mogły; biegł ("biek"), biegła, biegło, biegli, biegły. "Run" optionally has the suffix -ną before the infinitive suffix (biegnąć), but including it in biegł is not recommended.

6.13 For iść, idę, idziesz (go/come [on foot]), the l-forms have an entirely different root: szedł ("szet"), szła, szło, szli, szły.

7. The future of nie ma is nie będzie. Like nie ma, nie będzie makes the sentence impersonal, i.e., lacking a subject in the nominative case. Thus, while Będą na to pieniądze (There will be money for that) is a normal subject-predicate sentence with a nominative-case subject and an agreeing predicate, its negation, Nie będzie na to pieniędzy (There won't be any money for that), replaces the nominative-case subject with a genitive-case expression and the agreeing predicate with a uniform nonagreeing nie będzie. Similarly, Ja jutro będę na zebraniu (I'll be at the meeting tomorrow) is negated as Mnie jutro na zebraniu nie będzie.