La lingua di lavoro cambia nella sessione plenaria.

Italian uses the definite article much more often than English. In a sentence like this, la lingua di lavoro means the working language as a known or relevant thing in that context.

In English, we often drop the article in more abstract phrases, but Italian usually keeps it:

• la lingua
• il lavoro
• la sessione

So La lingua di lavoro is the natural way to say the working language.

Di lavoro literally means of work, but in natural English it usually becomes working or used for work.

So:

• lingua di lavoro = working language
• literally: language of work

This noun + di + noun structure is very common in Italian. It is used to define or classify something:

• orario di lavoro = work schedule
• ambiente di lavoro = work environment
• strumenti di lavoro = work tools

Here, di lavoro tells you what kind of lingua it is.

Because lingua and linguaggio are not the same.

• lingua = a language, such as Italian, English, French, or the language used in a meeting
• linguaggio = language in the broader sense of style, register, code, or system of expression

For example:

• La lingua italiana = the Italian language
• linguaggio tecnico = technical language
• linguaggio del corpo = body language

So lingua di lavoro is correct because it refers to an actual language used for communication.

Cambia is the third-person singular present tense of cambiare.

The subject is la lingua di lavoro, which is singular, so the verb is singular too:

• la lingua di lavoro cambia = the working language changes

Present tense in Italian can cover several ideas depending on context:

• a general fact: changes
• something happening now: is changing
• sometimes even a scheduled or regular occurrence

So cambia is a very normal choice here.

Because nella is the normal contraction of in + la.

Italian commonly combines prepositions with definite articles:

• in + il = nel
• in + la = nella
• in + lo = nello
• in + i = nei
• in + le = nelle

So:

• nella sessione plenaria = in the plenary session

You should generally not say in la sessione in standard Italian.

It can suggest either, depending on context.

In many cases, in + event/time expression in Italian is naturally understood as in / during:

• nella riunione
• nella lezione
• nella conferenza

So nella sessione plenaria can mean:

• in the plenary session
• during the plenary session

If you want to stress duration more explicitly, Italian could also use durante la sessione plenaria.

Because in Italian, adjectives often come after the noun, especially when they are classifying or descriptive in a straightforward way.

So:

• sessione plenaria = plenary session

This is the normal order. Putting the adjective first is usually unusual here and may sound literary, emphatic, or simply wrong in this expression.

Many institutional or formal phrases work this way:

• seduta pubblica
• riunione straordinaria
• assemblea generale

So sessione plenaria is the standard collocation.

Yes. Italian word order is more flexible than English, although the original sentence is the most neutral.

Neutral order:

• La lingua di lavoro cambia nella sessione plenaria.

Other possible orders:

• Nella sessione plenaria, la lingua di lavoro cambia.
• Cambia la lingua di lavoro nella sessione plenaria.

These alternatives can shift emphasis:

• starting with Nella sessione plenaria highlights the setting
• starting with Cambia gives more focus to the change itself

But the original version is a very natural, standard sentence.

Yes. Plenaria is directly related to English plenary and has a similar formal meaning.

A sessione plenaria is a full session involving all participants or members, rather than a smaller committee or subgroup meeting.

So if you know the English institutional term plenary session, this is a very close match.

A simple pronunciation guide is:

La LING-gwa dee la-VOR-o CAM-bya NEL-la ses-SYO-ne ple-NA-ria

A few useful notes:

• gli is not in this sentence, so pronunciation is fairly straightforward
• lingua has two syllables: lin-gua
• cambia sounds like CAM-bya
• plenaria has the stress on na: ple-NA-ria

If you read it smoothly: La lingua di lavoro cambia nella sessione plenaria.