Sur place ou à emporter, said in half a second, is the part that stops you.

The same handful of exchanges, every trip, each one over before you have finished decoding it.

• At the pharmacie

  You need a body part, a duration and then the dose, and the dose arrives as one sentence with nothing in front of you to point at. Deux comprimés matin et soir pendant cinq jours, said once, is the whole test.

• Prices and numbers at speed

  Soixante-quinze, quatre-vingt-douze: French builds its numbers out of arithmetic, and catching one said fast is a different skill from reading it. In Belgium and Switzerland the same figures arrive as septante and nonante.

• Marseille, Dakar, Montreal

  Ask for directions in four French-speaking cities and you get four accents, four speeds and some different words. Quebec adds the -tu question particle and vowels that Paris simply does not use.

• Complaining without being rude

  A wrong charge, a missed connection, a room that is not the one booked. The grammar is the conditional and the fixed polite formula — je voudrais savoir si, il y aurait moyen de — and it has to come out calmly.

• Tu, vous and getting it wrong

  France keeps vous with strangers for longer than Quebec does. Switching to tu too early sounds forward, keeping vous everywhere sounds stiff, and each switch changes the verb ending you then have to produce.

• When they switch to English

  Three words in a strong accent at a Paris counter and the assistant switches to English to be helpful. Holding the exchange in French mostly means answering quickly enough that switching never occurs to them.

Most of a trip runs on a few short exchanges, and the hard half of each one is the reply.

So the practice leans on the ear: hearing it once, at the speed it is really said, and answering before the silence does the work for you.

• Understanding the reply rather than only delivering your own line, because the reply is where the exchange usually stalls.
• The twenty-four-hour clock that every timetable and confirmation uses, heard once — dix-huit heures quarante, not six-forty.
• Polite framing that keeps a request from sounding like an order: je voudrais, est-ce que vous auriez, excusez-moi de vous déranger.
• Recognising the dropped ne and the syllables that vanish with it — chais pas, y a pas, t'as vu — so ordinary speech stops sounding like a separate language.
• Pardon, vous pouvez répéter: getting something said again straight away, before the exchange has moved past the part you missed.

Where this leaves you short

Two limits. You need French already — nothing here starts from zero, and a correction has nothing to work on if you cannot yet assemble the sentence. And the voice you practise against is neutral metropolitan French, so Marseille, Abidjan and Montreal will each still be an adjustment when you land.