Changer vs. se changer
In French, both changer and se changer revolve around the concept of to change, but their usage is distinct. The key difference lies in whether the subject is changing something else or changing itself, specifically its clothes.
Changer
A2This is a standard verb that means to change or to alter. It is used when the subject changes something or someone else (a direct object). It can also be used intransitively when something changes on its own, like the weather or an opinion.
Je dois changer les piles de la télécommande.
(I have to change the remote control's batteries.)
Nous allons changer notre itinéraire de voyage.
(We are going to change our travel itinerary.)
Le temps a beaucoup changé aujourd'hui.
(The weather has changed a lot today.)
Elle a décidé de changer de coiffure.
(She decided to change her hairstyle.)
Tu ne peux pas changer le passé.
(You cannot change the past.)
Pouvez-vous me changer ce billet de 20 euros ?
(Can you change this 20 euro bill for me?)
Se changer
A2This is a reflexive verb, identifiable by the pronoun se. Its primary and most common meaning is 'to change one's clothes'. The action of changing is performed by the subject on themselves. In some contexts, it can also mean to be transformed into or to turn into.
Je rentre à la maison pour me changer avant la fête.
(I'm going home to change (my clothes) before the party.)
Va te changer, tes vêtements sont mouillés.
(Go get changed, your clothes are wet.)
Après le sport, il se change toujours rapidement.
(After sports, he always gets changed quickly.)
Il fait froid, je vais me changer et mettre un pull.
(It's cold, I'm going to get changed and put on a sweater.)
Dans le conte, la citrouille se change en carrosse.
(In the fairy tale, the pumpkin changes into a carriage.)
L'eau se change en glace à zéro degré.
(Water changes into ice at zero degrees.)
Summary
In short, use changer when you are changing an external object, a plan, or your mind (e.g., changer une roue - to change a tire). Use se changer when you are specifically changing your own clothes (e.g., je vais me changer - I'm going to get changed). The reflexive pronoun se is the key indicator that the action applies to the subject itself.