Paul paie tous les frais du voyage.

Both paie and paye are correct spellings of the same verb form.

• The verb is payer (to pay).
• In the present tense, for je / tu / il / elle / on, you can write:
  • je paie or je paye
  • tu paies or tu payes
  • il/elle/on paie or paye

In modern French, paie is a bit more common in writing, and many textbooks teach paie first. In speech, they are pronounced the same: [pɛ] (like peh).

In French, a noun can be the subject of the verb directly, just like in English.

• Paul paie tous les frais du voyage.
  = Paul is the subject.

You only use a subject pronoun (il, elle, etc.) instead of a noun, not together with a full noun unless you’re emphasizing with a dislocation, e.g.:

• Paul, il paie tous les frais du voyage. (spoken, more emphatic: Paul, he’s paying all the expenses of the trip.)

But in a neutral sentence, you just say Paul paie …, not Il Paul paie ….

Paie is the present indicative, 3rd person singular of payer.

French present tense covers both English:

• Paul pays all the expenses of the trip.
• Paul is paying all the expenses of the trip.

Context tells you which English form to use; French doesn’t make a grammatical distinction here.

Because frais is a masculine plural noun.

• Masculine plural: tous les (tous les frais)
• Feminine plural: toutes les (toutes les questions, toutes les choses)

So:

• un frais (rare)
• des frais → tous les frais

Here les frais means expenses / costs / charges related to something (here, the trip).

Nuances:

• les frais: often used for practical or administrative expenses:
  • les frais de voyage (travel expenses)
  • les frais de scolarité (tuition fees)
• les dépenses: more general spending, expenditures, often money actually spent.
• les coûts: costs, sometimes more technical or economic.

In this sentence, les frais is very natural and standard for “expenses (of the trip)”.

In practice, les frais is almost always used in the plural when talking about money:

• les frais du voyage (the expenses of the trip)
• les frais médicaux (medical expenses)

There is a singular un frais, but it’s rare and usually appears in fixed, more technical or legal expressions. For everyday French about money, you just learn les frais as a fixed plural noun = expenses.

You could say Paul paie les frais du voyage, and it would mean “Paul pays the expenses of the trip.”

Adding tous emphasizes all of them:

• Paul paie les frais du voyage.
  → Paul pays the trip expenses (no emphasis on completeness).
• Paul paie tous les frais du voyage.
  → Paul pays all the expenses of the trip (suggests nothing is left for others to pay).

So tous is like English all for emphasis.

Du is the contraction of de + le.

• de + le voyage → du voyage

French always contracts:

• de + le → du
• de + les → des

So you must say:

• les frais du voyage (not de le voyage)
• les frais des vacances (not de les vacances)

Both can be used, but they’re not exactly the same:

• les frais du voyage
  → literally “the expenses of the trip”
  This links the expenses directly to the trip as something that belongs to or comes with it.

• les frais pour le voyage
  → “the expenses for the trip”
  Focuses more on the purpose: expenses that are for the trip (to make it possible, to prepare, etc.).

In this sentence, les frais du voyage is more idiomatic and natural.

Both relate to travel, but:

• un voyage = a trip, journey (the whole experience: before, during, after; includes stay, activities, etc.)
• un trajet = a route, journey in the sense of the path from point A to point B, usually more limited in time and space.

So:

• les frais du voyage → all expenses related to the trip (transport, accommodation, food, etc.)
• les frais du trajet → expenses related just to the ride/drive/flight (tickets, fuel, tolls, etc.)

In most contexts like holidays or business trips, les frais du voyage is more natural.

There is: it’s included in du.

• English: the expenses of the trip
• French: les frais du voyage
  (du = de + le → of the)

So the French structure is:

• les frais du voyage = les frais de le voyage = the expenses of the trip

French doesn’t use a separate word like of; it uses de (here contracted to du).

Approximate pronunciation (standard French):

• Paul → pohl (like “pole” but with a shorter, pure vowel)
• paie → peh [pɛ]
• tous les → too lay
• frais → freh [fʁɛ]
• du → dy (like “dew” but with rounded lips)
• voyage → vwah-yahzh

Full sentence (rough guide):
Paul paie tous les frais du voyage.
→ pohl peh too lay freh dy vwah-yahzh.

There is usually a liaison between:

• tous and les → you hear the s: tooz les.

No, not in normal French. The natural order is:

Subject – Verb – Object (and its complements)

So:

• Paul paie tous les frais du voyage. ✅

Something like Paul paie du voyage tous les frais sounds unnatural or incorrect in standard French. You generally keep tous les frais du voyage together as one noun phrase after the verb.

It’s neutral, standard French.

You can use this sentence:

• In speech or writing
• In everyday conversation or in relatively formal contexts

If you wanted something a bit more formal, you might hear:

• Paul prend à sa charge tous les frais du voyage.
• Paul règle tous les frais du voyage.

But Paul paie tous les frais du voyage is perfectly correct and widely used.