Péřový míček i plastový míček létají přes badmintonovou síť.

Because the subject is actually two things joined together:

• Péřový míček
• i plastový míček

Together they form a compound subject, so Czech uses a plural verb. That is why you get létají and not létá.

Here i means something like and or as well as.

So:

• péřový míček i plastový míček = the feather shuttlecock and the plastic shuttlecock

Be careful: i can also mean also / even in other contexts. But in this sentence, it is simply connecting two nouns.

Yes, Czech could say:

• Péřový i plastový míček létají...

That is possible, and it means essentially the same thing.

Repeating míček makes the sentence a little clearer and can emphasize that we are talking about two separate types. It is very natural Czech.

They are in the nominative singular because they are the subjects of the sentence.

You can see the basic dictionary form here:

• péřový míček
• plastový míček

Even though there are two singular nouns, together they create a plural subject, which is why the verb is plural.

Because after přes, Czech normally uses the accusative case.

The basic form is:

• badmintonová síť = nominative

But after přes, it changes to accusative:

• přes badmintonovou síť

So both words change as needed:

• badmintonová → badmintonovou
• síť stays síť in form here, even though the case is accusative

This is common with some feminine nouns: the noun itself may look the same in nominative and accusative, while the adjective shows the case clearly.

Přes usually means across, over, or through, depending on context.

Here it means something like over/across the badminton net:

• létají přes badmintonovou síť = they fly over/across the badminton net

So přes is the natural preposition for movement from one side to the other.

Not exactly.

• letí usually means is flying / flies as a single action or movement
• létají comes from létat, which often suggests repeated, habitual, or general flying

In this sentence, létají fits well because it describes a general fact: these shuttlecocks fly over the net.

So it sounds more like:

• they fly
• they go flying
• they fly back and forth

rather than one single flight at one exact moment.

They are adjectives describing míček.

• péřový = feather / feathered
• plastový = plastic

They both agree with míček, which is a masculine inanimate singular noun, so the adjective ending is -ový in the nominative singular masculine form.

That is why you have:

• péřový míček
• plastový míček

In everyday Czech, míček literally means small ball, but it is also commonly used for the badminton shuttlecock in many contexts.

Depending on context, Czech speakers may also use more specific sports vocabulary, but péřový míček and plastový míček are perfectly understandable and natural, especially when distinguishing materials.

Because grammatical gender in Czech is a property of the noun itself, and síť is a feminine noun.

You just have to learn it as part of the word:

• ta síť = the net

That feminine gender is why the adjective agrees as feminine:

• badmintonová síť
• badmintonovou síť

Yes. Czech word order is fairly flexible.

For example, you could also say:

• Péřový míček i plastový míček létají přes síť.
• Přes badmintonovou síť létají péřový míček i plastový míček.

The original order is neutral and straightforward. Other orders may shift the emphasis a little, but the grammar still works.

The tricky part is ř, a famous Czech sound. It is not exactly like any single English sound.

A rough guide:

• pé-řo-vý

The ř is something like a rolled or buzzing r mixed with a zh sound. English speakers usually need practice with it.

You do not need perfect pronunciation immediately. If you say something close to rzh, people will often still understand you.

Also note the long vowels:

• péřový has long é
• míček has long í
• síť has long í

Long vowels matter in Czech, so try to make them clearly longer than short vowels.