Final answer:
The sentence 'Ellos son de mexicanas' is incorrect as written. The correct sentence should be 'Ellos son mexicanos' to indicate that 'they' are Mexican (male). If you want to refer to a group of females, you would use the feminine form 'Ellos son mexicanas'.
Step-by-step explanation:
The sentence Ellos son de mexicanas is incorrect as written.
The correct sentence should be Ellos son mexicanos to indicate that 'they' are Mexican (male).
If you want to refer to a group of females, you would use the feminine form Ellos son mexicanas.
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