Learn Polish: Gospodarz i gospodyni to państwo Kaczmarkowie. - The host and the hostess are Mr. and Mrs. Kaczmarek.

When referring to a married couple or a family, Polish uses the plural form of the surname. For surnames that act like standard nouns (usually ending in a consonant), the plural ending for mixed-gender groups is -owie. Notice also that the e in the singular "Kaczmarek" disappears when adding the ending. This is called a "fleeting e," which commonly drops out when suffixes are added to words ending in -ek.

How does the word państwo work in this sentence?

Państwo has a few meanings in Polish, but here it acts as a formal title for a mixed-gender married couple, translating to "Mr. and Mrs." When placed right before a plural surname like Kaczmarkowie, it shows respect and clarifies that you are talking about the couple as a single unit.

Why is there no verb like są (are) in this sentence? Can we just use to?

Yes! When you are saying "Noun A is Noun B" to identify someone or something, Polish frequently uses to as a shortcut. When you use to, both sides of the sentence stay in the basic Nominative case. If you wanted to use the actual verb są, the second half of the sentence would have to change into the Instrumental case (są państwem Kaczmarkami), which is correct but slightly heavier and less common for simple identification.

Is gospodyni the regular feminine form of gospodarz?