had been proofing
Past perfect progressive conjugation of proof.
See all conjugations of proof

proof

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500+ learners.
NOUN
(evidence)-la prueba
Synonyms for proof
evidence
las pruebas
affirmation
la confirmación
attestation
la autenticación
attestation
el testimonio
authentication
la autenticación
clue
la pista
testimonial
la recomendación
testimony
el testimonio
validation
la validación
vindication
la justificación
warrant
la justificación
witness
el testimonio
NOUN
(printing, photography)-la prueba
Synonyms for proof
photograph
la fotografía
picture
la imagen
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