Spotkanie potrwa jeszcze godzinę.

• Spotkanie = the meeting; it is the subject.
• potrwa = will last; this is the verb.
• jeszcze = still / yet / another / more, depending on context. Here it means another / more.
• godzinę = an hour, in the accusative case.

So structurally, it is basically:

Meeting + will last + another + hour

Because potrwa comes from the perfective verb potrwać. In Polish, perfective verbs do not normally have a present meaning in forms like this; their so-called present forms usually refer to the future.

So:

• trwa = is lasting / lasts from imperfective trwać
• potrwa = will last from perfective potrwać

This is very common in Polish aspect.

They are related, but not identical.

• trwać is imperfective: it describes duration as an ongoing process, with no built-in endpoint.
• potrwać is perfective: it presents the event as lasting for a certain bounded period.

In this sentence, potrwa suggests the meeting will continue for another hour as one whole time span.

A rough contrast:

• Spotkanie trwa = The meeting is going on / is lasting
• Spotkanie potrwa jeszcze godzinę = The meeting will last another hour

Here jeszcze means another or more.

So jeszcze godzinę means:

• another hour
• one more hour

In other contexts, jeszcze can mean:

• still — Jeszcze śpi = He is still sleeping
• yet — Jeszcze nie wiem = I don’t know yet

But with a duration phrase like this, another / more is the natural reading.

Because Polish usually uses the accusative case for a duration of time after verbs like trwać, czekać, spać, pracować, and so on.

So:

• godzina = nominative, the basic dictionary form
• godzinę = accusative singular

Compare:

• Czekam godzinę = I’m waiting for an hour / I wait an hour
• Spałem całą noc = I slept all night
• Spotkanie potrwa jeszcze godzinę = The meeting will last another hour

Because Polish often expresses duration without a preposition. The accusative case itself can show the idea of for.

So English says:

• for another hour

Polish simply says:

• jeszcze godzinę

That is a very normal Polish pattern.

Because in Polish, with time expressions, the numeral one is often omitted when it is obvious.

So:

• godzinę can mean an hour
• jedną godzinę is also possible, but it sounds more emphatic

You might use jedną if you want contrast or emphasis, for example:

• Nie dwie, tylko jedną godzinę = Not two, only one hour

In a neutral sentence, godzinę is enough.

Yes. That is also correct and natural.

There is a small difference in feel:

• Spotkanie potrwa jeszcze godzinę = a compact, very natural way to say The meeting will last another hour
• Spotkanie będzie trwało jeszcze godzinę = also The meeting will be lasting / will last another hour, using the future of the imperfective verb trwać

In many everyday contexts, both are fine.
The version with potrwa often feels a bit more concise and bounded.

It means one more hour from the relevant reference point, not the total duration of the whole meeting.

So if the meeting is already happening, Spotkanie potrwa jeszcze godzinę means:

• The meeting will last another hour
• The meeting will continue for one more hour

If you wanted to say the total duration is one hour, you would usually express that differently, depending on context.

Yes. Polish word order is fairly flexible, and changing it usually changes emphasis, not the core meaning.

The neutral version is:

• Spotkanie potrwa jeszcze godzinę.

Other possible orders include:

• Jeszcze godzinę potrwa spotkanie.
  This emphasizes another hour.

• Spotkanie jeszcze potrwa godzinę.
  This puts more focus on jeszcze, the idea that it will still continue.

For a learner, the original order is the safest and most neutral.

Spotkanie is a neuter noun and here it is in the nominative singular, because it is the subject of the sentence.

Its dictionary form is also spotkanie.

You can see its neuter gender more clearly in other structures, for example:

• To spotkanie było długie. = This meeting was long.
• Dobre spotkanie = a good meeting

In potrwa, the verb form does not visibly show gender, so the noun ending is the main clue here.