When to use "s' " and "se"

Question

When using reflexive verbs, is there any hint whether to use the prefix s' or se? For example: s'aimble and se laver

Answer 1

The rules are those of elision.

The final 'e' of 'se' is replaced by an apostrophe when the following word starts with a vowel or a mute 'h'.

Answer 2

The rule is : before a vowel remove the [ə]

aimer: s' aimer

perdre: se perdre

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