Protips: The little things you learn to pro up your French

En and dans both mean ‘in’ in English but are employed in slightly different contexts and expressions. When used in relation to time, their meanings vary subtly. ‘En’ is used to mark the period in which an action is performed. ‘Dans’ is used to indicate the amount of time that will elapse before an event takes place. Note the difference in these statements:

J’ai écrit ma dissertation en deux semaines – I wrote my essay in two weeks

Le prochain train va partir dans dix minutes – The next train will leave in ten minutes

The first example describes the amount of time the speaker used to complete the task, namely writing their essay. In the second example, the speaker is saying that the train will be arriving after the ten minutes has elapsed.

If we rewrite the first example with a slightly different focus it might yield something like: Je vais écrire ma dissertation dans deux semaines. This time, the speaker is saying they will wait for two weeks to pass before starting to write the essay.