Questionner vs. interroger

In French, the verbs 'questionner' and 'interroger' both relate to the act of asking questions but are used in slightly different contexts.

Questionner

'Questionner' generally means to ask a series of questions or to inquire. It is often used in a more informal or general sense.
Il n'arrête pas de me questionner sur mes projets d'avenir.
(He keeps questioning me about my future plans.)
Tu devrais questionner ton cœur pour comprendre tes vrais désirs.
(You should question your heart to understand your true desires.)
Les enfants adorent questionner sur tous les sujets imaginables.
(Children love to ask questions about every imaginable subject.)

Interroger

'Interroger', on the other hand, typically conveys a more formal questioning, often used in contexts such as police interviews, surveys, or academic study. It can imply a search for precise information or clarification.
La police a interrogé plusieurs témoins après le vol.
(The police interrogated several witnesses after the theft.)
L'étude interroge les effets du réchauffement climatique sur l'agriculture.
(The study investigates the effects of global warming on agriculture.)
Le professeur a interrogé l'élève sur la leçon dhier.
(The teacher quizzed the student on yesterday's lesson.)

Summary

'Questionner' and 'interroger' both involve asking questions, but 'questionner' is more for general inquiry and is less formal, while 'interroger' is usually more structured and formal, typically aiming to acquire specific information or responses.