No explanation of when devoir can be used for "need to" instead of "must"

Question

How could you say "He needs a day off." ?
 
I answered:
 
Il a besoin d'un jour de congé.
*Il doit un jour de congé*

Accepted Answer

Hi Patrick,
The verb -
 devoir quelquechose à quelqu'un =  to owe something to someone

Elle me doit de l'argent = She owed me money
Je lui dois beaucoup = I owe a lot to him/her

The verb devoir to mean obligation or something you have to do will be followed by a verb and not a noun -

Je dois aller au supermarché = I must go to the supermarket 
Nous devons rendre visite à notre tante = We need/have to visit our aunt

Hope this helps!

Answer

Bonjour Patrick,In one way or another, this type of question has been discussed many times on the forum.https://progress.lawlessfrench.com/questions/search?search=devoirhttps://progress.lawlessfrench.com/questions/search?search=avoir+besoinTry them both  -  they are not the same set of answersHope this helpsBonne journéeJim

Answer

@Cecile, thanks for replying, but unless I'm missing something, your answer doesn't address the question. The one example is use of devoir to mean "owe", which I understand. The other basically says that it means "must/have to", but does not address when to use it to mean "need to"

@Jim, thanks for your response as well. I looked at the links and neither of them appear to address the question.

It would be really nice if Kwiziq could do a quick lesson on it, as it seems to be a recurring problem.

Thank you both for taking the time to respond.

Answer

Bonjour Patrick,
When you want to express "to need [something]" (i.e. "to need help/money" for example), you use "avoir besoin de [something]" as explained in the lesson content: "As for expressing to need [something], it will always be avoir besoin de [quelque chose]". Using "devoir" here means something very different (see examples below).
Il a besoin d'un jour de congé = He needs a day off
Il doit un jour de congé (à ses employés) = He owes a day off (to his employees)
I hope this is helpful.
Bonne journée !

Answer

After discussing this with a French speaking friend it seems that if besoin is followed by a verb, you can use the devoir form to mean "need to". If it is followed by a noun you cannot