Медичне страхування потребує довідки.

Because страхування is a neuter noun in Ukrainian, and adjectives must agree with the noun in gender, number, and case.

• страхування = neuter singular
• so the adjective must also be neuter singular: медичне

Compare:

• медична довідка = a medical certificate/note (довідка is feminine)
• медичне страхування = medical insurance (страхування is neuter)

It is in the nominative case because it is the subject of the sentence — the thing that requires something.

The structure is:

• Медичне страхування = the subject
• потребує = requires
• довідки = of a certificate / certificate (in the required case after this verb)

So медичне страхування is the thing doing the requiring.

Because the verb потребувати / потребує usually takes the genitive case.

The dictionary form is:

• довідка = certificate, note, official document

But after потребує, it becomes:

• довідки = genitive singular

So:

• потребує довідки = requires a certificate / requires some kind of certificate

This is one of the important patterns to remember:

• потребувати кого? чого? = to need / require someone or something

Examples:

• потребую допомоги = I need help
• потребує часу = it requires time
• потребують підтримки = they need support

The base form is потребувати = to need / to require.

потребує is:

• 3rd person singular
• present tense
• imperfective

So it means:

• he/she/it needs
• requires

Here the subject is страхування, which is grammatically singular, so the verb is singular too:

• страхування потребує

It can mean either, depending on context.

In this sentence, English often prefers requires:

• Medical insurance requires a certificate

But grammatically, потребує is also related to the idea of needing.

A rough guide:

• need = often more personal or general
• require = often more formal or official

Since медичне страхування is a formal system or policy, requires sounds especially natural.

Довідка usually means an official note, certificate, or document issued by some institution, doctor, employer, school, etc.

It does not always mean a general reference or information sheet. In many real-life contexts, довідка is the kind of paper you submit to prove something officially.

Depending on context, it could be:

• a doctor’s note
• a certificate
• an official confirmation document

So learners should not always translate довідка mechanically as just reference.

Because Ukrainian has no articles.

English distinguishes between:

• a certificate
• the certificate

Ukrainian does not mark that directly with a word like a/the. The meaning comes from context.

So довідки could correspond to:

• a certificate
• the certificate
• some documentation

depending on the situation.

Yes, Ukrainian word order is fairly flexible.

This version is the most neutral:

• Медичне страхування потребує довідки.

It simply states the fact.

You could also say:

• Довідки потребує медичне страхування.

This puts more emphasis on довідки — as if contrasting what needs a certificate.

Because Ukrainian marks grammatical roles through case endings, the word order can move around more freely than in English. But the neutral, textbook order is often:

• subject + verb + object/complement

It is singular.

Even though in English insurance can feel like a mass noun, in Ukrainian страхування is grammatically a singular neuter noun.

That is why the verb is singular:

• страхування потребує not
• страхування потребують

It is a noun derived from a verb.

• страхувати = to insure
• страхування = insuring / insurance

This kind of noun is very common in Ukrainian. Many nouns ending in -ння are verbal nouns that describe a process, activity, or institution-related concept.

So медичне страхування literally has the sense of medical insuring / medical insurance, but in actual usage it simply means medical insurance.

Yes. That is a very natural alternative, but it means the same idea from a different angle.

• Медичне страхування потребує довідки. = Medical insurance requires a certificate.

• Для медичного страхування потрібна довідка. = A certificate is needed for medical insurance.

The second version is often more conversational and may sound a little more natural in everyday speech, depending on context.

Notice the grammar change:

• для медичного страхування = for medical insurance
• потрібна довідка = a certificate is needed

Great question — the form довідки can indeed be ambiguous out of context.

It can be:

• genitive singular of довідка
• nominative plural of довідка

But here the verb helps you.

Because потребує usually requires the genitive, the natural reading is:

• довідки = genitive singular

So here it means of a certificate / a certificate, not certificates as the subject.

Context and verb pattern are what tell you which meaning is intended.

Yes, it sounds fairly formal or administrative.

Words like:

• медичне страхування
• потребує
• довідка

are very common in official, bureaucratic, medical, and institutional language.

In everyday conversation, people might choose a slightly simpler or more practical phrasing, but this sentence is completely normal Ukrainian.