In English we use a variety of words to express that we are able or not able to do something, when something is allowed, and when something must be done or must not be done. Often we use what’s known as a modal verb, something like ‘can’, ‘must’, ‘should’ or ‘will’. In Polish there are also a number of words you can choose to express these functions, but here the rules are a little more rigid. Unlike our ‘can’, for example, there are two separate verbs in Polish for to ‘be able to physically’ and to’ know how to’, and it is this type of variation that you’ll need to learn the different ways to express these functions.
Saying You Can (are able to)
Like I said, in Polish there are two different words for being able to do something, and these are divided by distinguishing between physical ability and mental ability (to ‘be able to’ and ‘to know’). The first of these is móc (to be able to), which expresses physical ability, and the second is umieć (to know how to).
So, if you wanted to say ‘I can swim’, móc is used, but in its first person form mogę (I can), always followed by the infinitive form of the verb that expresses what it is you can do: mogę pływać (I can swim).
Remember if you want to talk about what someone else can do, the ending of móc will need to change to reflect the new subject (możesz (you can), on/ona może (he/she can)).
Similarly to say you ‘know how to’ do something, it’s the first person form of umieć that’s used with the infinitive form of the verb that says what it is you know: Umiem pisać (I can [know how to] write).
Asking Permission and Prohibiting
In Polish you can use two words to ask for permission, either można or wolno. Again, these are both used with the infinitive form of the verb that represents what it is you are asking permission to do. Generally speaking wolno is heavier than można, and asks if something is permitted rather simply possible: Czy można tu pływać? (Can one swim here?), Czy wolno palić (Am I allowed to smoke?).
Accordingly answering with tak, można (yes, you can) or nie można (you can’t), is much less prohibitive than using wolno (it is allowed) or nie wolno (it is not allowed). Incidentally, it’s the latter that you will hear in Polish parks with naughty dogs and helpless dog owners.
The Polish equivalent to the English ‘must’ is ‘musieć’ and it’s used in a very similar way. Again, it’s important to know the verb endings for the first, second and third person singular and plural forms, as this is how you will use ‘musieć’ to address other people and yourself. Here are some examples:
Muszę zrobić to jutro. (I must do this tomorrow.)
Musisz zrobić to jutro. (You must do this tomorrow.)
On/ona musi zrobić to jutro. (He/she must do this tomorrow.)
Musimy zrobić to jutro. (We must do this tomorrow.)
Musicie zrobić to jutro. (You [pl] must do this tomorrow.)
Oni/one muszą zrobić to jutro. (They must do this tomorrow.)
In addition to issuing a command, ‘musieć’ can be used, like its English counterpart, to suppose or guess something: Musisz być znudzony (you must be bored).
As you can see there are loads of functions associated with just these few words, and learning them can mean you will be able to express a whole new range of meanings: So,
Musicie się tego nauczyć (you must learn them!).