W moim podręczniku każdy rozdział kończy się krótką rozmową i małym sprawdzianem.

Because po w / in often requires the locative case when it means in or inside.

So:

• podręcznik = dictionary form, nominative
• w podręczniku = in the textbook → locative
• mój changes to moim to match the noun in case, gender, and number

So:

• mój podręcznik = my textbook
• w moim podręczniku = in my textbook

It is the locative singular.

The phrase w moim podręczniku uses:

• w
  • locative
• moim = locative singular masculine/neuter
• podręczniku = locative singular of podręcznik

This is a very common pattern in Polish:

• w domu = in the house
• w sklepie = in the shop
• w podręczniku = in the textbook

Because każdy rozdział is the subject of the sentence, so it stays in the nominative case.

The sentence is built around:

• każdy rozdział = every chapter
• kończy się... = ends...

So literally:

• Every chapter ends...

Here:

• każdy = every
• rozdział = chapter

Both are in the nominative singular masculine because they form the subject.

In this sentence, kończyć się means to end or to finish.

Polish often uses się in verbs where English does not. Here it creates a meaning similar to:

• ends
• comes to an end
• finishes

So:

• kończyć = to end something / to finish something
• kończyć się = to end, to come to an end

Examples:

• Film kończy się o dziewiątej. = The film ends at nine.
• Rozdział kończy się rozmową. = The chapter ends with a dialogue.

So się is part of the verb expression here and should be learned together with it.

Because kończyć się commonly takes the instrumental case to express what something ends with.

In English we say:

• ends with a short dialogue and a small quiz

In Polish, the idea of with is built into the case here, so no separate word for with is needed.

That is why you get:

• krótka rozmowa → krótką rozmową
• mały sprawdzian → małym sprawdzianem

Both are in the instrumental singular.

Because the adjectives must match the nouns they describe, and the nouns have different genders.

1. rozmowa is feminine

So in the instrumental singular:

• krótka rozmowa → krótką rozmową

Typical feminine instrumental singular adjective ending:

• -ą

2. sprawdzian is masculine

So in the instrumental singular:

• mały sprawdzian → małym sprawdzianem

Typical masculine/neuter instrumental singular adjective ending:

• -ym or -im

So the endings differ because of gender.

They are both instrumental singular, but they belong to different noun genders and declension patterns.

Feminine noun

• rozmowa → rozmową

A very common feminine instrumental singular pattern is:

• -a → -ą

Masculine noun

• sprawdzian → sprawdzianem

A common masculine instrumental singular ending is:

• -em

So both nouns are in the same case, but they change differently because they are different types of nouns.

Not in this sentence if you want the same natural structure.

After kończyć się, Polish normally uses the instrumental directly:

• kończy się krótką rozmową
• kończy się małym sprawdzianem

Using z would sound wrong here.

Compare:

• Rozdział kończy się rozmową. = The chapter ends with a dialogue.
• Rozdział jest z rozmową. = The chapter is with a dialogue.
  This is a different idea and not natural in the same way.

So after kończyć się, learn the pattern:

• kończyć się + instrumental

Yes, Polish word order is more flexible than English.

The sentence begins with W moim podręczniku to set the context first:

• In my textbook, every chapter...

This is very natural.

You could also say:

• Każdy rozdział w moim podręczniku kończy się krótką rozmową i małym sprawdzianem.

That also makes sense.

The original version puts slight emphasis on in my textbook as the setting. Polish often moves elements around for emphasis, rhythm, or style, while the cases keep the meaning clear.

Yes, normally każdy means each / every and is used with a singular noun.

So:

• każdy rozdział = every chapter
• każda lekcja = every lesson
• każde zadanie = every exercise

Even though the meaning refers to all members of a group, the grammar is singular.

That is why the verb is also singular:

• każdy rozdział kończy się...

not a plural verb.

Sprawdzian usually means a quiz, test, or check-up exercise, especially in a school or textbook context.

It is related to the verb sprawdzać = to check.

In this sentence, mały sprawdzian suggests something like:

• a small quiz
• a short test
• a little review exercise

It does not necessarily mean a big formal exam. In a textbook context, quiz or short test is often a good way to understand it.

No. Podręcznik specifically means a textbook or coursebook.

So:

• książka = book
• podręcznik = textbook/coursebook

That is why W moim podręczniku means In my textbook rather than just In my book.

Here are the main dictionary forms:

• w = in
• mój = my
• podręcznik = textbook
• każdy = every / each
• rozdział = chapter
• kończyć się = to end
• krótki = short
• rozmowa = conversation / dialogue
• i = and
• mały = small
• sprawdzian = quiz / test

This is useful because many of the forms in the sentence are inflected:

• moim comes from mój
• podręczniku comes from podręcznik
• krótką comes from krótki
• rozmową comes from rozmowa
• małym comes from mały
• sprawdzianem comes from sprawdzian

In this textbook context, dialogue is often the more natural translation.

Although rozmowa literally means conversation, language-learning textbooks often use it for a short spoken exchange between people, which English learners often call a dialogue.

So in context:

• krótka rozmowa = a short dialogue / a short conversation

Both are possible, but dialogue often sounds more natural for textbook material.