Dokładny opis pomaga mi zrozumieć zadanie.

Because dokładny is an adjective and it has to agree with opis.

Here, opis is:

• masculine
• singular
• nominative (because it is the subject)

So the adjective also takes the masculine singular nominative form: dokładny.

If the noun changed, the adjective would change too:

• dokładny opis = a detailed/precise description
• dokładna instrukcja = a detailed instruction
• dokładne zadanie = a precise task

It is in the nominative case.

In this sentence, dokładny opis is the subject — the thing that performs the action of pomaga.

You can think of the structure as:

Dokładny opis + pomaga + mi + zrozumieć zadanie
The detailed description + helps + me + understand the task

So dokładny opis stays in the nominative.

Because the subject is singular.

The subject is opis = description, which is one thing, so the verb must also be singular:

• opis pomaga = the description helps
• opisy pomagają = the descriptions help

So pomaga is the 3rd person singular form of pomagać.

Both mi and mnie can mean to me / me, but they are used a little differently.

In this sentence, mi is natural because it is the short, unstressed form. After pomagać, that is usually what you want:

• To pomaga mi zrozumieć zadanie. = This helps me understand the task.

Mnie is usually used:

• for emphasis
• after prepositions
• when you want contrast

For example:

• To pomaga mnie, nie tobie. = This helps me, not you.
• Dla mnie = for me

So here, mi is the normal choice.

Mi is in the dative case.

The verb pomagać normally takes the person being helped in the dative:

• pomagać mi = help me
• pomagać ci = help you
• pomagać mu = help him
• pomagać nam = help us

So in this sentence, mi means to me grammatically, even though in English we just say helps me.

This is an aspect question.

• rozumieć = to understand, to be understanding, to understand in a general/ongoing sense
• zrozumieć = to understand, but in the sense of coming to understand or grasping something successfully

In this sentence, zrozumieć fits well because the idea is that the description helps you reach understanding of the task.

So:

• pomaga mi zrozumieć zadanie = helps me understand / helps me come to understand the task

If you said pomaga mi rozumieć, that would sound more like helping you understand things in general or on an ongoing basis.

Because Polish infinitives do not use a separate word like English to.

In English:

• to understand

In Polish:

• zrozumieć

The infinitive meaning is built into the verb form itself, usually ending in -ć.

So:

• zrozumieć = to understand
• czytać = to read
• robić = to do / to make

Here, zadanie is in the accusative singular because it is the direct object of zrozumieć.

You understand what?
zadanie

A useful thing to know is that for many neuter nouns, the nominative and accusative singular look the same.

So:

• nominative: zadanie
• accusative: zadanie

That is why the form does not change here.

Because zadanie is a neuter noun, and in the singular, neuter nouns usually have the same form in the nominative and accusative.

So even though its grammatical role changes, the word still looks the same:

• To jest zadanie. = This is a task.
  (nominative)

• Rozumiem zadanie. = I understand the task.
  (accusative)

This is very common with neuter nouns in Polish.

Because pomagać is the imperfective verb, and it is the normal choice for a present-tense statement like this.

• pomagać = imperfective
• pomóc = perfective

In Polish, a perfective verb normally does not have a true present tense meaning. Its present-looking forms usually refer to the future.

So:

• pomaga = helps / is helping
• pomoże = will help

That is why pomaga is correct here.

The word order can change, but the version given is the most neutral and natural.

Dokładny opis pomaga mi zrozumieć zadanie. is a straightforward sentence:

• subject first
• then verb
• then pronoun/object material

Polish word order is more flexible than English because case endings show the grammatical roles. But changing the order can change the emphasis.

For example:

• Dokładny opis pomaga mi zrozumieć zadanie. = neutral
• Zadanie pomaga mi zrozumieć dokładny opis. = completely different meaning
• Dokładny opis pomaga zrozumieć mi zadanie. = possible, but less natural than the original

So yes, word order is flexible, but not random.

It can, depending on context, but its core meaning is closer to:

• exact
• precise
• thorough
• careful

In many contexts, dokładny opis can be translated naturally as a detailed description, especially if the point is that the description is thorough enough to help.

A nearby word is szczegółowy, which also often means detailed:

• szczegółowy opis = detailed description
• dokładny opis = precise/thorough description

In real translation, both can sometimes sound natural in English, but they are not always exactly the same in nuance.

Zadanie is a very common Polish word with several related meanings, including:

• task
• exercise
• assignment
• problem to solve

The exact meaning depends on context.

So in different situations:

• in school, zadanie might mean exercise or assignment
• at work, it might mean task
• in maths, it might mean problem

In this sentence, task is a very natural general translation.

A rough pronunciation guide is:

dok-WAHD-nih OH-pees po-MAH-ga mee zro-zoo-MYECH za-DAH-nye

A few notes:

• ł sounds roughly like English w
• ś / ć / ń / ź / dź are soft consonants; here the final -ć in zrozumieć is a soft ch-like sound
• ci / ni / zi before vowels often sound softened
• rz usually sounds like the zh sound in measure
• ie in zrozumieć and zadanie is part of the softening and vowel pattern, not pronounced exactly like English ee

A more Polish-like approximation would be:

doh-KWAD-nih OH-pees poh-MAH-gah mee zroh-zoo-MYECH zah-DAH-nye

Yes, you could. That is also correct Polish.

Compare:

• Dokładny opis pomaga mi zrozumieć zadanie.
• Dokładny opis pomaga mi w zrozumieniu zadania.

The first one uses pomagać + infinitive:

• helps me understand the task

The second one uses pomagać w + noun:

• literally helps me in the understanding of the task

Both are correct, but the original sentence with zrozumieć is often more direct and natural in everyday use.