Reflexive verbs in Spanish are truly curious and interesting.
You can read an article that explains it well right here on our blog in the articles section.
The reason is that not only are verbs reflexive when they are governed by the same subject and object, but also verbs that require reflexive pronouns to change their meaning or verbs whose action occurs within the same subject.
Practice a bit. Match the verbs from the first column with their opposites from the second column:
Acercarse (to approach)
Inclinarse (to lean)
Extraviarse (to get lost)-
Irse (to leave)
Caerse (to fall)-
/
Quedarse (to stay)
Alejarse (to move away)
Hallarse (to find oneself)
Levantarse (to stand up)
Erguirse (to straighten up)