Learn Hardcore French: Paul monte sur le toit pour réparer la fuite. - Paul goes up onto the roof to fix the leak.

It’s present tense, 3rd person singular of monter. French present covers both simple and progressive aspects, so Paul monte can mean either “Paul is climbing” or “Paul climbs,” depending on context.

Why is it sur le toit and not au toit?

Use sur for being physically on top of a surface: sur le toit = “on the roof.”
À/au indicates “to/at” a place in general (e.g., au grenier, à l’étage), and you don’t stand “at” a roof in French. To say “on the roof,” French needs sur.

Can I replace sur le toit with a pronoun?

Yes, use y for places introduced by sur, dans, à, etc.
Example: Paul y monte pour réparer la fuite.
You can also replace la fuite with la: Paul y monte pour la réparer.

Why la fuite and not une fuite?

La fuite = “the leak,” i.e., a specific or known leak (already identified in context).
Une fuite = “a leak,” introducing it as new information.
Without prior context, une fuite is often more neutral.

What else can fuite mean besides “leak”?

Une fuite d’eau / de gaz = a water/gas leak.
La fuite can also mean “escape/flight” (as in running away): la fuite du prisonnier. Context disambiguates it.

Is pour + infinitive the right way to express purpose here?

Yes. Pour + infinitif expresses purpose when the subject is the same:
Paul monte ... pour réparer ...
If the subject changes, use pour que + subjonctif:
Paul monte sur le toit pour que le plombier puisse réparer la fuite.
Synonyms: afin de + infinitif, more formal.

Can I omit pour and say ... monte ... réparer ...?

No. In French, you can’t drop pour in purpose clauses. You must say pour réparer (or afin de réparer).

Can I move the purpose clause to the front?

Yes: Pour réparer la fuite, Paul monte sur le toit.
This is natural and puts emphasis on the reason. Add a comma after the fronted clause.

What auxiliary does monter take in the passé composé: être or avoir?

Both, depending on usage:

Intransitive (no direct object): use être.
Example: Paul est monté sur le toit. (agrees with the subject: monté/montée.)
Transitive (with a direct object): use avoir.
Example: Paul a monté l’échelle. (no agreement unless a preceding direct object forces it.)

What’s the difference between monter sur, monter dans, and monter à?

monter sur
- surface: sur le toit, sur la table (on top of).
monter dans
- container/vehicle: dans le bus, dans la voiture (to get into).
monter à
- destination/level: à l’étage, au premier, or idiomatic locations (monter à Paris).
  Using the wrong preposition can change the meaning (e.g., monter sur le bus = climb onto the roof of the bus).

Could I say réparer la fuite du toit instead of sur le toit?

It’s understandable but less idiomatic. Prefer:

réparer une fuite sur le toit (where the leak is), or
réparer la toiture / une fuite de toiture when you mean the roof covering in general.
Du toit sounds like a possessive “the roof’s leak,” which is not the most natural phrasing.

Is réparer la fuite idiomatic, or should I use another verb?

Réparer une fuite is fine and common. Alternatives: boucher or colmater une fuite (to plug/seal a leak), depending on the context.

What’s the nuance between monter, grimper, and aller here?

monter: neutral “go up/climb.”
grimper: “clamber/climb with effort,” often informal or emphasizing difficulty.
aller: generic “go,” without the upward nuance.
So monter sur le toit is the default if there’s any upward movement.

How do I pronounce the tricky words?

Paul [pɔl] (short o, like “pall” without the length)
monte [mɔ̃t] (nasal o; final -e silent)
sur [syʁ] (French u [y])
le [lə]
toit [twa] (sounds like “twa”)
pour [puʁ]
réparer [ʁepaʁe] (accent aigu, each e sounded)
fuite [fɥit] (“fweet”: French u + i makes a [ɥi] glide)

Are there any liaisons in the sentence?

No required liaisons. You’ll typically say:
[mɔ̃t syʁ lə twa puʁ ʁepaʁe la fɥit]
No liaison between monte and sur, nor between sur and le.

What are the genders of toit and fuite, and how do they affect the articles?

toit is masculine: le toit.
fuite is feminine: la fuite.
Articles and any agreeing adjectives must match these genders.

Why is there no article before Paul?

Personal names in French don’t take an article in standard usage: Paul, Marie, etc. (Regional speech may sometimes add one, but that’s not standard.)

Can I shorten the sentence with pronouns correctly?

Yes:

Replace the place: Paul y monte.
Replace the object of réparer: Paul monte sur le toit pour la réparer.
Both: Paul y monte pour la réparer.
Remember: in simple tenses, object/adv. pronouns go before the verb they depend on; with an infinitive, they go before the infinitive.