Příloha je potvrzení o příjmech.

Příloha most commonly means attachment or enclosure in this kind of formal/document context.

So in a sentence like Příloha je potvrzení o příjmech, it means that the attachment/enclosed document is an income certificate/confirmation.

Be aware that příloha can also mean other things in other contexts, such as:

• side dish in food contexts
• appendix in books or documents

Context tells you which meaning is intended.

Je is the 3rd person singular form of být (to be), meaning is.

So:

• Příloha = the attachment
• je = is
• potvrzení o příjmech = confirmation/certificate of income

Because příloha is singular, Czech uses je.

Compare:

• Příloha je důležitá. = The attachment is important.
• Přílohy jsou důležité. = The attachments are important.

Czech has no articles, so it does not have separate words corresponding to English a/an and the.

That means Příloha je potvrzení o příjmech could be understood as:

• The attachment is an income certificate
• An attachment is the income certificate
• The enclosure is a confirmation of income

In real life, context usually makes it clear which English article makes most sense.

Potvrzení means confirmation, certificate, or document confirming something, depending on context.

It is a neuter noun. In this sentence, it is in the nominative singular form.

A useful thing to notice is that many Czech neuter nouns end in -í, especially abstract or document-type words, for example:

• potvrzení = confirmation/certificate
• rozhodnutí = decision
• osvědčení = certificate

Here potvrzení refers to a document: a written confirmation of income.

The preposition o has several meanings, but here it means something like about or concerning.

So:

• potvrzení o příjmech = confirmation/certificate about income
• more natural English: income certificate, proof of income, or confirmation of income

In Czech, some nouns regularly combine with o to express what something is about.

For example:

• kniha o Praze = a book about Prague
• zpráva o nehodě = a report about the accident
• potvrzení o studiu = certificate of study / confirmation of enrollment
• potvrzení o příjmech = confirmation of income

Because the preposition o requires the locative case.

The basic form is:

• příjmy = incomes / earnings

After o, it changes to the locative plural:

• o příjmech = about incomes/earnings

So the pattern is:

• nominative plural: příjmy
• locative plural: o příjmech

This is very common in Czech: prepositions often force a specific case.

That is a very natural question for an English speaker.

In Czech, příjem can mean income, receipt, or earnings, and in formal phrases Czech often uses the plural příjmy where English prefers singular income.

So:

• potvrzení o příjmech is standard Czech
• natural English translation is usually proof of income or income certificate, not necessarily proof of incomes

This is one of those places where Czech and English package the idea differently.

In this sentence, potvrzení is in the nominative.

Czech can use both nominative and instrumental after forms of být, depending on style, meaning, and sentence type. But in simple identifying sentences like this, nominative is very common and natural.

So:

• Příloha je potvrzení o příjmech. = natural

You may also encounter instrumental in other kinds of predicate constructions, but for a learner, it is enough to recognize that this sentence uses a normal nominative predicate noun.

Yes, Czech word order is flexible.

The sentence as written:

• Příloha je potvrzení o příjmech.

This is a neutral way to say The attachment is the income confirmation.

Czech word order often reflects topic and focus rather than strict grammar roles. You could change the order, but the emphasis would change too.

For example:

• Potvrzení o příjmech je příloha.
  = The income certificate is the attachment.
  This sounds less neutral and shifts attention.

So the given order is the most straightforward if you are identifying what the attachment is.

A rough pronunciation guide:

• Příloha ≈ PZHEE-lo-ha
• je ≈ ye
• potvrzení ≈ pot-vr-zeh-nee
• o ≈ o
• příjmech ≈ PZHEE-yeh-mekh

A few important sounds:

• ř in pří- is the famous Czech ř, a special sound with no exact English equivalent.
• í is a long ee sound.
• ch is like the ch in Scottish loch or German Bach, not like English chair.

If pronunciation is your goal, the hardest parts here are usually pří- and -ch.

Yes, it is a very common formal phrase.

You will often see similar document phrases in Czech:

• potvrzení o studiu = certificate of study / proof of enrollment
• potvrzení o zaměstnání = employment confirmation
• potvrzení o bydlišti = proof of residence
• potvrzení o příjmech = proof of income

So this is a useful pattern to learn:

• potvrzení o + locative

It is especially common in administration, banking, schools, and official paperwork.

Yes. Depending on context, příjmy can be translated as:

• income
• earnings
• receipts (in some accounting contexts)

In this sentence, the most natural English idea is usually income.

So potvrzení o příjmech might be translated as:

• proof of income
• income certificate
• confirmation of earnings

The best English choice depends on the situation, but the Czech is standard in all these official meanings.