Kdo krmí štěně?

Because kdo is the subject form of who.

In Kdo krmí štěně?, the unknown person is the one doing the action of feeding, so Czech uses kdo.

• Kdo krmí štěně? = Who is feeding the puppy?
• Koho krmíš? = Who are you feeding?

So:

• kdo = who as the subject
• koho = whom / who as the object

Krmí is a present-tense form of the verb krmit, which means to feed.

The infinitive is:

• krmit = to feed

In this sentence, krmí means feeds / is feeding.

It is the form used for:

• he feeds
• she feeds
• it feeds
• they feed

Czech often relies on context rather than separate helping words.

It can mean either one, depending on context.

Czech present tense often covers both:

• Who feeds the puppy?
• Who is feeding the puppy?

If the situation is happening right now, English often uses is feeding.
If it is more general or habitual, English may use feeds.

So the Czech sentence itself does not force that distinction.

Because Czech does not form questions the same way English does.

English often needs an auxiliary verb:

• Who is feeding the puppy?
• Who does feed the puppy? (less common in normal speech)

Czech usually just uses:

• a question word, such as kdo
• the normal verb form

So Kdo krmí štěně? is completely normal Czech. No extra word like does or is is needed.

Here štěně is in the accusative, because it is the direct object of the verb krmí.

It is the thing being fed.

So:

• kdo = the doer
• krmí = feeds
• štěně = the thing/person/animal receiving the action

Because štěně is a neuter noun, and for many neuter nouns, the nominative and accusative singular have the same form.

So:

• nominative: štěně
• accusative: štěně

That is why the object does not visibly change here, even though it is in the accusative.

Štěně is neuter.

That is very common for Czech words for young animals. For example, many baby-animal words are neuter.

This matters for agreement later on:

• malé štěně = a small puppy
• štěně bylo doma = the puppy was at home

Notice the neuter forms malé and bylo.

Because Czech has no articles.

So štěně can mean:

• a puppy
• the puppy

The exact English translation depends on context.

That is why one Czech sentence can match more than one English version.

Yes. Czech word order is fairly flexible.

The neutral order here is:

• Kdo krmí štěně?

But you could also hear:

• Kdo štěně krmí?

That version puts a little more attention on štěně, as if contrasting it with something else.

So both are possible, but Kdo krmí štěně? is the most straightforward, neutral version.

A learner-friendly approximation is:

• Kdo ≈ gdo
• krmí ≈ kr-mee
• štěně ≈ shtye-nye

A few important points:

• In kdo, the k is often pronounced more like g because of the following d.
• í in krmí is a long vowel.
• š sounds like English sh.
• ň is a soft n sound, similar to Spanish ñ.

The real Czech pronunciation is a bit subtler than English spelling can show, but those approximations are a good start.

Yes. Krmit is an imperfective verb.

That means it is good for:

• ongoing action
• repeated action
• general present meaning

So Kdo krmí štěně? can mean Who is feeding the puppy? or Who feeds the puppy?

A related perfective verb is nakrmit. If you say:

• Kdo nakrmí štěně?

that usually means something more like:

• Who will feed the puppy?
• Who will feed the puppy completely / get the feeding done?

So krmit and nakrmit are not interchangeable.