I've encountered this quiz: translate this sentence: "Marie worked for ten hours yesterday". The answer excludes this option: Marie a travaillé en dix heures hier.
Why can't I use the word "en"? It's mentioned here: En vs Dans with time (French Prepositions of Time)
"En expresses the length of time something takes to be done."
You can't use en to express how long something takes or for how long you've been doing something. This is normally accomplished using pendant, pour, and durant.
En is used as a temporal proposition in two cases:
(1) Expressing a time frame within which something has to happen ("within")
Tu dois finir en 10 minutes. -- You havet to finish within 10 minutes.
Don't confuse this with the following sentence using dans:
Tu dois finir dans 10 minutes. -- You have to finish in 10 minutes.
Note that in an imprecise use of the English language, "within" and "in" are often used interchangably. French keeps this distinction clear, however,
(2) To specify a time with months and seasons:
Nous reviendrons des vacances en juliiet. -- We're returning from vacation in July.
Ils font du ski en hiver. -- They go skiing in winter.
Dracus,
En (or dans) are not correct here.
The difference here is effectively the same as the difference in English between
' did something for 10 hours ' - pendant/durant -
and
' did something in/within 10 hours ' - dans/en.
" When talking about time or durations introduced by in - in two hours, in 1876,... - in French you will either use dans or en. "
Don't have an account yet? Join today
Test your French to the CEFR standard
Find your French level