Trawnik przed blokiem jest mokry po deszczu.

Because przed changes case depending on meaning.

In this sentence, przed blokiem means in front of the apartment block as a location, so przed takes the instrumental case.

• blok = nominative
• blokiem = instrumental

So:

• przed blokiem = in front of the block
• idę przed blok = I’m going to the area in front of the block

A very common pattern in Polish is:

• location → often instrumental after przed
• movement toward a place → often accusative after przed

Blok usually means an apartment block, block of flats, or a large residential building, especially in Central/Eastern European contexts.

So przed blokiem does not usually suggest a random block in the English sense. It specifically sounds like in front of the apartment building.

Because mokry is an adjective and it must agree with trawnik.

Trawnik is:

• singular
• masculine
• in the nominative case

So the adjective also appears in the matching form:

• mokry trawnik = a wet lawn

Compare:

• trawa jest mokra = the grass is wet
• okno jest mokre = the window is wet

The ending changes with gender:

• masculine: mokry
• feminine: mokra
• neuter: mokre

Jest is the 3rd person singular form of być = to be.

So:

• Trawnik ... jest mokry = The lawn ... is wet

In the present tense, Polish often omits to be in some informal or stylistic contexts, especially in short labels or headlines, but in a normal sentence like this, jest is the standard and natural form.

Trawnik is in the nominative case because it is the subject of the sentence.

The sentence structure is basically:

• Trawnik = subject
• jest = verb
• mokry = predicate adjective
• przed blokiem and po deszczu = extra information about place and circumstance/time

So trawnik stays in the basic dictionary form here.

Because the preposition po here means after, and in this meaning it takes the locative case.

• dictionary form: deszcz = rain
• locative form: deszczu

So:

• po deszczu = after the rain

This is a very useful pattern:

• po obiedzie = after lunch
• po pracy = after work
• po filmie = after the film

In natural English translation, it often means after the rain or after rainfall, depending on context.

Polish does not have articles like a or the, so deszczu by itself does not tell you whether English should use the. You choose that from context.

So po deszczu can be understood as:

• after the rain
• after rain
• after it rained

Yes. Polish word order is more flexible than English because cases show grammatical relationships.

The neutral order here is:

• Trawnik przed blokiem jest mokry po deszczu.

But other orders are also possible, for example:

• Po deszczu trawnik przed blokiem jest mokry.
• Przed blokiem trawnik jest mokry po deszczu.

These versions may sound slightly different in emphasis, but the meaning stays basically the same.

English usually relies much more on fixed word order than Polish does.

Because Polish has no articles.

English says:

• the lawn
• the block
• the rain

Polish simply says:

• trawnik
• blok
• deszcz

Whether something is a or the is understood from context.

So Trawnik przed blokiem jest mokry po deszczu can naturally correspond to:

• The lawn in front of the block is wet after the rain.

Not exactly.

• trawnik = lawn, a maintained grassy area
• trawa = grass

So this sentence is specifically about a lawn, not just grass in general.

Compare:

• Trawnik jest mokry. = The lawn is wet.
• Trawa jest mokra. = The grass is wet.

They are both additional phrases giving more information:

• przed blokiem = where the lawn is
• po deszczu = under what circumstances / after what event it is wet

Polish often places such phrases after the noun or after the main clause, but there is flexibility.

You can think of the core sentence as:

• Trawnik jest mokry. = The lawn is wet.

Then extra details are added:

• przed blokiem = in front of the block
• po deszczu = after the rain

These are tricky because of consonant clusters.

A rough English-friendly guide:

• przed ≈ pshet
• blokiem ≈ BLO-kyem
• deszczu ≈ DESH-choo or DE-shchoo

A few useful sound notes:

• rz usually sounds like zh / sh depending on voicing
• szcz is a cluster something like shch
• ie after a consonant often softens it a bit

So the whole sentence is roughly:

TRAV-nyek pshet BLO-kyem yest MO-kri po DESH-choo

That is only approximate, but it can help at the beginning.

In standard full Polish, jest is expected here.

Without jest, the sentence sounds incomplete in ordinary speech. You might see this kind of omission in:

• notes
• headlines
• very compressed style

But for normal learning and normal conversation, use:

• Trawnik przed blokiem jest mokry po deszczu.

That is the safe, correct version.