Final answer:
The sentence 'Ella se maquilla' is grammatically incorrect.
Step-by-step explanation:
The grammatically incorrect sentence is: Ella se maquilla.
The correct sentence would be: Ella se maquilla.
This sentence is incorrect because the reflexive pronoun 'se' should be placed before the verb 'maquilla', like in the correct sentence 'Ella se maquilla'.
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