French phrase
Puis-je ~ sans réservation ?
Meaning
May I ___ without a reservation?
When to use it
A polite way to ask permission without a reservation. It has a relatively formal tone and suits public facilities.
Example dialogue
Puis-je utiliser la salle d'étude sans réservation ?
May I use the study room without a reservation?
Non, il faut réserver à l'avance.
No, you need to make a reservation in advance.