Learn Hardcore French: Sur le campus, la cafétéria est pleine à midi. - On campus, the cafeteria is full at noon.

sur = on / on the grounds of
- Sur le campus literally matches English on campus and is the usual expression.
à
- place = in / at a town, country, or some institutions
  - à l’université = at university
  - You could say au campus, but it is much less common than sur le campus and can sound less natural.
dans = inside something that has clear physical limits (a room, building, box)
- dans la salle, dans le bâtiment.

A campus is more like an area or grounds, so French speakers normally say sur le campus to mean on campus.

Why is it le campus (masculine) and not la campus?

Campus is a borrowed word from English/Latin, and in French borrowed nouns usually become masculine by default, unless there’s a strong reason to make them feminine.

So:

le campus (masculine singular)
un campus moderne
les campus universitaires

You almost never see la campus; that would be considered incorrect.

Is la cafétéria the same thing as le café or la cantine?

They are related but not identical:

la cafétéria
- Self-service style place with trays, counters, several choices of food.
- Common in universities, companies, big stores.
- Very close to English cafeteria.
le café
- A café / coffee shop, usually with table service.
- People go there for drinks and simple meals, but it’s not specific to a university.
la cantine
- A canteen, usually for schools or workplaces (especially primary/secondary schools).
- More basic, very institutional, often associated with children’s school lunches.

On a university campus, la cafétéria is usually the natural word.

Why is it la cafétéria est pleine and not le cafétéria est plein?

Two separate points:

Gender of cafétéria
- la cafétéria is feminine.
- Many nouns ending in -ia are feminine (la pizzeria, la pharmacie, la librairie (different ending but similar idea of feminine “shop/place” words)).
Agreement of the adjective
- The adjective must agree in gender and number with the noun it describes.
- Subject: la cafétéria → feminine singular
- Adjective: pleine (feminine singular of plein)
- So you must say: La cafétéria est pleine.

Le cafétéria est plein is grammatically wrong because cafétéria is not masculine.

What exactly does pleine mean here? Is it just “full of people”?

In this context, pleine means full, usually full of people when talking about a place:

La cafétéria est pleine = The cafeteria is full (of people).

You could make it more explicit:

La cafétéria est pleine de monde. = The cafeteria is full of people.

But in everyday speech, pleine alone is enough; everyone understands it means full of customers/students.

Could I say La cafétéria est bondée à midi instead of pleine? What’s the difference?

Yes, you can, and it changes the nuance slightly:

pleine
- Neutral: all the seats are taken, it’s at capacity.
- Could be busy, but not necessarily uncomfortable.
bondée
- Stronger: packed / crammed / jam‑packed.
- Suggests there are too many people; it feels overcrowded.

So:

La cafétéria est pleine à midi.
→ It’s full at noon (normal, expected).
La cafétéria est bondée à midi.
→ It’s really, really crowded, almost too much.

Why is it à midi and not au midi or le midi?

French uses different forms depending on the meaning:

à midi = at noon (a specific time)
- On se retrouve à midi. = We meet at noon.
- In your sentence: pleine à midi = full at noon.
le midi = midday / lunchtime in general
- Le midi, je mange avec mes collègues. = At lunchtime (in general), I eat with my colleagues.
- It refers to a habitual time period, not a specific clock time.
au midi
- Very rarely used in modern French for time; normally considered incorrect in this context.
- au is the contraction of à + le, but here you don’t say à le midi for time.

So for a specific hour (12:00), it must be à midi.

Could I also say vers midi instead of à midi?

Yes, but the meaning changes slightly:

à midi = at noon, right around 12:00.
vers midi = around noon, approximately (maybe 11:45–12:15, not exact).

So:

La cafétéria est pleine à midi.
→ Exactly at noon, it’s full.
La cafétéria est pleine vers midi.
→ It gets full around noon, not necessarily at 12:00 sharp.

Why does the sentence start with Sur le campus? Could I put that part later?

French word order is quite flexible for information like place and time. All of these are grammatically possible:

Sur le campus, la cafétéria est pleine à midi.
- Emphasis on the location first: On campus, the cafeteria is full at noon.
La cafétéria est pleine à midi sur le campus.
- Grammatically OK, but sounds heavier and less natural in speech.
La cafétéria est pleine sur le campus à midi.
- Possible, but also a bit clumsy.
More natural everyday structure:
- La cafétéria du campus est pleine à midi.
  → The campus cafeteria is full at noon.

Starting with Sur le campus is a common way to set the scene (location) before giving the main statement.

Why is there an article before both nouns: le campus, la cafétéria? Could I drop them?

Normally you keep the article:

Sur le campus (not Sur campus)
La cafétéria est pleine (not Cafétéria est pleine)

French almost always uses an article with common nouns:

le, la, les (definite)
un, une, des (indefinite)

Leaving the article out, like in English “on campus” or “school starts at noon”, is not standard in French.

The only common exception is certain set expressions or titles (e.g. aller à l’école, parler de travail in some contexts), but campus and cafétéria here need their articles.

How do you pronounce Sur le campus, la cafétéria est pleine à midi?

Rough phonetic guide (approximate English sounds):

Sur → “syr” (like English sir, but with rounded lips and a French u sound)
le → “leuh” (short, neutral vowel)
campus → “kahn‑pyss” (final s pronounced; cam like French camp, not “kampyus”)
la → “la”
cafétéria → “ka‑fay‑tay‑ree‑a” (stress is quite even in French)
est → “eh” (the st is silent)
pleine → “plen” (like plen in plenty, with a nasal n)
à → “a” (like a in father)
midi → “mee‑dee”

Spoken fairly smoothly:

Sur le campus, la cafétéria est pleine à midi.
→ Syr leuh kahn‑pyss, la ka‑fay‑tay‑ree‑a eh plen a mee‑dee.

Is there any difference between saying Sur le campus, la cafétéria est pleine à midi and Sur le campus, la cafétéria est toujours pleine à midi?

Yes, adding toujours changes the meaning:

… est pleine à midi.
→ It is full at noon (this time, or as a general description, but without insisting on regularity).
… est toujours pleine à midi.
→ It is always full at noon (every day, regularly).
→ Emphasizes that this is a constant, repeated situation.

Both are correct; choose toujours if you want to stress that it happens every day.