Rano karmię rybki i królika, a wieczorem sypię ziarno chomikowi.

Polish usually leaves out subject pronouns when the verb already makes the subject clear.

• karmię = I feed
• sypię = I pour/scatter/give

Because both verbs are in the 1st person singular, adding ja would usually be unnecessary unless you want extra emphasis, like Ja karmię rybki... = I’m the one who feeds the fish...

That ending shows 1st person singular present tense, so it means I am doing the action.

• karmić → karmię = I feed
• sypać → sypię = I pour/scatter

This is a very common pattern in Polish verb conjugation, although the exact stem can change depending on the verb.

In this sentence, it most naturally describes a habit or routine:

• Rano karmię... = In the morning I feed...
• wieczorem sypię... = in the evening I give/scatter...

Polish present tense can mean both right now and regularly, and the time expressions here make it sound like a daily routine.

Because Polish uses different fixed adverbial expressions for times of day.

• rano = in the morning
• wieczorem = in the evening

They do not match each other perfectly in form, so it is best to learn them as set expressions.

Related words:

• ranek = morning as a noun
• wieczór = evening as a noun

But in everyday speech, when talking about when something happens, you commonly use:

• rano
• wieczorem

Rybki is the plural of rybka, which is a diminutive form of ryba.

So:

• ryba = fish
• rybka = little fish, or more naturally in context, pet fish

In a sentence about feeding animals at home, rybki sounds very natural because it suggests aquarium fish or small pet fish.

Also, as the direct object here, rybki stays the same in form because it is a feminine plural accusative, and for that type of noun, the accusative plural is the same as the nominative plural.

Because królik is the direct object of karmię, so it must be in the accusative case.

• nominative: królik = rabbit
• accusative: królika = rabbit as the thing being fed

For masculine animate nouns in Polish, the accusative singular usually looks like the genitive singular, which is why you get królika.

Because here the hamster is the recipient of the grain, not the direct object.

In:

• sypię ziarno chomikowi

the grammar is:

• ziarno = what is being poured/given → direct object → accusative
• chomikowi = to whom it is given → indirect object → dative

So:

• nominative: chomik
• dative: chomikowi = to the hamster

If you said chomika, that would be accusative/genitive, and it would not fit this structure.

Ziarno is the direct object of sypię, so it is in the accusative. But because ziarno is a neuter singular noun, its accusative form is the same as its nominative form.

• nominative: ziarno
• accusative: ziarno

So the form does not change, even though the case does.

Yes, but in Polish ziarno can work a bit like a mass noun here, meaning something like grain/feed/seed in a general sense.

So:

• sypię ziarno chomikowi = I give/pour grain for the hamster

If you wanted to emphasize individual seeds, you might use a plural form such as ziarna in some contexts. But ziarno is very natural when talking about animal food in a general way.

Both can often translate as and, but they are not used in exactly the same way.

• i simply joins things together
• a often links two parts while also making a contrast or shift in topic

Here:

• Rano karmię rybki i królika, a wieczorem sypię ziarno chomikowi.

The a helps express a contrast in time:

• in the morning ...,
• and then/in contrast in the evening ...

So a is very natural here.

Because in Polish, coordinating conjunctions like a are normally preceded by a comma when they connect two clauses.

So the comma in:

• ..., a wieczorem sypię...

is standard Polish punctuation.

Polish word order is fairly flexible, although some versions sound more natural than others.

This sentence could be rearranged, for example:

• Wieczorem sypię chomikowi ziarno.
• Rano karmię królika i rybki...

The original version is natural because it starts with the time expressions:

• Rano...
• wieczorem...

That makes the routine very clear.

Because the two verbs work differently.

• karmić kogoś/coś = to feed someone/something
  • direct object in the accusative
  • karmię królika
• sypać coś komuś = to pour/scatter something for someone / give by pouring
  • thing in the accusative
  • recipient in the dative
  • sypię ziarno chomikowi

So the grammar changes because the verb changes.

Yes, that would also be grammatical, but it means something slightly different in structure.

• karmię chomika ziarnem = I feed the hamster with grain
• sypię ziarno chomikowi = I pour/scatter grain for the hamster

The first focuses on feeding as the overall action. The second focuses on the more physical action of pouring/scattering the grain.

Both can fit similar situations, but they are not exactly the same sentence.

Grammatically, it is definitely a diminutive form of ryba. But in real usage, diminutives in Polish are very common and do not always sound especially emotional in English terms.

In a pet context:

• rybki often just sounds natural for pet fish
• it can suggest smallness, affection, or simply everyday домашний-style wording

So although it literally comes from little fish, in context it may just be the normal, natural way to talk about aquarium fish.