a derechas – correctly
Tú nunca haces nada a derechas.
You never do anything correctly.
Ella no sabe hacer las cosas a derechas.
She doesn’t know how to do things correctly.
A derechas is always employed in the negative. You would not, for example, say “Hazlo a derechas.” Nor would it be correct to say “Hay que hacer todo a derechas.”
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