Problem je nestao.

Je is the 3rd person singular present form of biti (to be).

In Serbian, the usual past tense is built with:

• a form of biti
• plus a past participle

So:

• problem = the subject
• je = is/has as an auxiliary here
• nestao = disappeared / gone

Even though je literally comes from to be, in this sentence it is not translated as a separate is. It is just part of the Serbian past tense.

So Problem je nestao is structurally something like:

• The problem has disappeared or
• The problem disappeared

depending on context.

Because nestao agrees with the noun problem, which is masculine singular in Serbian.

The past participle changes for gender and number:

• masculine singular: nestao
• feminine singular: nestala
• neuter singular: nestalo
• plural masculine: nestali
• plural feminine/neuter: nestale / nestala depending on the standard pattern and context

Since problem is masculine singular, the correct form is nestao.

Examples:

• Greška je nestala. = The mistake disappeared. (greška is feminine)
• Pismo je nestalo. = The letter disappeared. (pismo is neuter)
• Problem je nestao. = The problem disappeared. (problem is masculine)

The infinitive is nestati.

So:

• nestati = to disappear, to vanish

The form nestao is the masculine singular past participle used in the past tense.

A very useful pair to know is:

• nestati = to disappear
• stati / ostati / postati are unrelated but may look a bit similar to learners, so do not confuse them

You may also see present-tense forms such as:

• nestane
• nestaju depending on person/number and context.

Nestati is perfective.

That means it usually refers to a completed event: something disappeared or was gone.

So Problem je nestao presents the disappearance as a finished fact.

If you want an ongoing, repeated, or habitual sense, Serbian often uses an imperfective verb instead, depending on the context. But in a sentence like this, nestati is the natural choice because it means the problem is now gone.

That is why this sentence feels very natural for:

• The problem disappeared
• The problem is gone now

Serbian has no articles like English a/an/the.

So problem can mean:

• a problem
• the problem

The exact meaning depends on context.

In this sentence, English will often use the problem because the speaker usually has a specific problem in mind:

• The problem disappeared.
• The problem is gone.

But Serbian does not need a separate word for the.

It is in the nominative singular, because it is the subject of the sentence.

The basic dictionary form is:

• problem = nominative singular

In Problem je nestao, the thing doing the action of disappearing is problem, so nominative is used.

For learners, this is a nice simple sentence because the subject stays in its basic form.

Yes, Serbian word order is fairly flexible, and Nestao je problem is possible.

However, the most neutral version is:

• Problem je nestao.

A reordered version can change emphasis:

• Nestao je problem. = emphasis on the fact that it disappeared / is gone
• Problem je nestao. = neutral statement about the problem

So the original sentence is the safest and most standard form for a learner.

Je is pronounced roughly like ye in English.

So:

• je ≈ ye

The whole sentence is approximately:

• PRO-blem ye ne-STAO

A few pronunciation notes:

• r in Serbian is trilled or tapped, not the English r
• j in Serbian sounds like English y
• ao in nestao is pronounced as two vowels together, not like a single English vowel sound

Because it is the start of a sentence.

The word problem itself is not normally a proper noun. It is only capitalized here because it comes first.

If it appeared in the middle of a sentence, it would usually be lowercase:

• Kažu da je problem nestao. = They say the problem disappeared.

Yes.

It can be used literally:

• a physical problem, object, or issue somehow disappeared

But more often it is used figuratively:

• a difficulty was resolved
• an obstacle is no longer there
• the issue is gone

So Serbian uses nestao much like English disappeared or went away, both in concrete and abstract situations.

Yes.

Depending on context, English might translate it as:

• The problem disappeared.
• The problem is gone.
• The problem has disappeared.

Serbian past tense here can correspond to different natural English choices. The Serbian sentence states a completed event, and English can phrase that in several ways depending on style and context.

Yes. Problem is a masculine noun.

In Serbian, many masculine nouns end in a consonant, and problem fits that pattern perfectly.

So:

• problem = masculine singular
• therefore: Problem je nestao

This is very common with loanwords and international words too:

• telefon
• program
• sistem
• problem

All of these are masculine nouns in Serbian unless there is some other reason for a different gender.