a true and final test of success
un vrai et ultime test du succès (un vrai et ultime test du succes)
"The real market will be the acid test for this invention."
"Le marché réel sera le test acide pour cette invention." (le marche reel sera **le test acide** pour cette invention)
People or things forgotten when not visible or present.
to speak at length in an excited or annoyed way
to analyze data in great detail
directly from the original or reliable source
to not pay attention to what is said
to take the lead in a race or competition