If Both 'En' and 'Dans' Mean 'In,' How Do You Use Them?

These two French prepositions are not interchangeable

man reading book on train
"Il a lu le livre en une heure." (He read the book in an hour.). Deux / Getty Images

In French, the prepositions en and dans both mean "in" and they both express time and location. But they are not interchangeable. Their usage depends on both meaning and grammar. 

How French Prepositions Work

In French, prepositions are generally words that link two related parts of a sentence. They are usually placed in front of nouns or pronouns to indicate a relationship between that noun or pronoun and a verb, adjective or noun that precedes it.

  • I'm talking to Jean. > Je parle à Jean.
  • She is from Paris. > Elle est de Paris.
  • The book is for you. > Le livre est pour toi.

These small but powerful words not only show relationships between words, they also refine the meanings of place (cities, countries, islands, regions and U.S. states) and time (as with pendant and durant), can follow adjectives and link them to the remainder of a sentence, can never end a sentence (as they can in English), can be difficult to translate into English and idiomatic, and can exist as a prepositional phrase such as au-dessus de (above), au-dessous de (below) and au milieu de (in the middle of).

Some are also used after certain verbs to complete their meaning such as croire en (to believe in), parler à (to talk to) and parler de (to talk about). Plus, preposition phrases can be replaced by the adverbial pronouns y and en.

The following guidelines and examples delineate how and when to use two of the trickier French prepositions: en and dans.

Notice how they link two related parts of each sentence. 

When to Use 'En'

1. En expresses the length of time an action happens. This means the verb is usually in the present or past tense, as in:

  • Je peux faire le lit en cinq minutes. > I can make the bed in five minutes.
  • Il a lu le livre en une heure. > He read the book in an hour.
  • J'ai appris à danser en un an. > I learned how to dance in a year.

2. En expresses the month, season or year when an action happens. Exception: au printemps.

  • Nous voyageons en Avril. > We travel in April.
  • Il arrivera en hiver. > He will arrive in the winter.

3. En can mean "in" or "to" when en is directly followed by a noun that doesn't need an article:

  • Vous allez en prison ! > You're going to prison! 
  • Il est en classe. > He's in school.

4. En can also mean "in" or "to" when used with some states, provinces and countries, such as:

  • J'habite en Californie > I live in California.
  • Je vais en France. >  I'm going to France.

When to Use 'Dans'

1. Dans indicates the amount of time before an action will occur. Note that this means the verb is usually in the present or future, as in:

  • Nous partons dans dix minutes. > We're leaving in 10 minutes.
  •  Il reviendra dans une heure. > He'll be back in an hour. 
  • Elle va commencer dans une semaine. > She's going to start in a week.

2. Dans refers to something that occurs within or during a decade, as in:

  • Dans les années soixantes...   In the sixties... 
  • Dans les années quatre-vingts... During the eighties...

3. Dans means "in" a location when followed by an article plus noun, such as:

  • Il est dans la maison. > He's in the house. 
  • Qu'est-ce qui est dans la boîte? > What's in the box?

4. Dans also means "in" or "to" with some states and provinces:

  • J'habite dans le Maine. > I live in Maine.
  • Je vais dans l'Ontario. > I'm going to Ontario.