In general terms monter/descendre is transitive (takes a direct object) and is thus conjugated with aller in the compound tenses when the past participle is is followed by a determiner (+noun) or where the direct object or object pronoun precedes the participle. Determiners are words such as definite and indefinite articles, demonstrative pronouns, possesive pronouns , numbers etc. which precede nouns.
J'ai monté l'escalier - I went up the stairs
Il a démonté sa souris d'ordinateur - he took his computer mouse to pieces
Elle a descendu dix livres de la étagère - she took down10 books from the shelf
Ils les ont descendues - They brought them down (eg suitcases)
La montagne que j'ai montée est belle
Monter/descentre is intransitive (takes an indirect object) and is thus conjugated with être in the compound tenses when the past participle is is followed by a preposition or by nothing, or where the indirect object pronoun precedes the participle.
Le prix de pain est monté - The price of bread has increased
Elle est montée dans sa chambre - She went up to bedroom
Thank you for your excellent answer. The only thing I would like to correct is the example in your intransitive section of the price of bread going up -
It would be:
Le prix du pain a monté. = The price of bread has risen.
It is an odd one but it is the same when you talk about the level of a river rising:
La Garonne a encore monté cette nuit. =The Garonne river's level rose again last night.
Les prix ont monté considérablement cette année. = Prices have risen sharply this year.
Hope this helps!
Sign in to submit your answer
Don't have an account yet? Join today
Test your French to the CEFR standard