Le train part dans soixante-dix minutes.

Part is the third-person singular present tense form of partir.

• je pars = I leave
• tu pars = you leave
• il/elle/on part = he/she/one leaves

Since le train is singular, French uses the same verb form as il/elle: part.

So the grammar is:

• Le train = subject
• part = present tense verb

French often uses the present tense for scheduled or expected future events, especially with things like trains, flights, classes, and timetables.

So Le train part dans soixante-dix minutes is completely natural, just like English can say:

• The train leaves in seventy minutes

French can also use a future form, such as Le train va partir dans soixante-dix minutes, but the simple present is very common for fixed schedules.

Here, dans means in, in the sense of after a certain amount of time.

So:

• dans soixante-dix minutes = in seventy minutes

This is different from expressing duration.

Compare:

• Le train part dans soixante-dix minutes = the departure happens seventy minutes from now
• Le train roule pendant soixante-dix minutes = the train travels for seventy minutes

So dans points to when something will happen, not how long it lasts.

In standard French, 70 is usually expressed as soixante-dix, literally sixty-ten.

This is part of the traditional French number system:

• 60 = soixante
• 70 = soixante-dix
• 71 = soixante et onze
• 72 = soixante-douze

A learner often notices that this is different from English because it is not built the same way as seventy.

Also, in some French-speaking regions, especially Belgium and Switzerland, people often say septante instead of soixante-dix.

After dans, when French gives an amount of time with a number, it normally uses the number directly:

• dans cinq minutes
• dans une heure
• dans soixante-dix minutes

You do not add an article like les here.

So dans soixante-dix minutes is the normal pattern for in + amount of time.

Yes. That is also correct.

Both are natural, but there is a slight difference in feel:

• Le train part dans soixante-dix minutes: very common for schedules and fixed events
• Le train va partir dans soixante-dix minutes: also correct, a bit more explicitly future

For a timetable or announced departure, the simple present part is especially common.

Le train means a specific train, the one already known from the situation or context.

French often uses the definite article when the speaker and listener both know which thing is being talked about, for example:

• the train on the board
• the train you are waiting for
• the train just mentioned in conversation

If you said un train, it would mean a train, which sounds less specific.

A simple pronunciation guide is:

luh tran par dan swa-sahn-dees mee-newt

A few helpful notes:

• train has a nasal vowel, so it does not sound like English train
• part: the t is usually silent
• dans also has a nasal vowel
• soixante-dix is pronounced roughly swa-sahn-dees
• minutes ends with a pronounced t sound: mee-newt

The main challenge for English speakers is usually the nasal sounds in train and dans.

Because the number is greater than one.

French works like English here:

• une minute = one minute
• deux minutes = two minutes
• soixante-dix minutes = seventy minutes

So the plural minutes is required.

Yes. That would also be correct.

• dans soixante-dix minutes
• dans une heure et dix minutes

Both mean the same amount of time. The first is more direct numerically, and the second breaks it into one hour and ten minutes.

French speakers may choose either one depending on style and context.