La acusación llamó al testigo para testificar en contra del supuesto asesino.The prosecution called the witness to testify against the alleged murderer.
A masculine noun is used with masculine articles and adjectives (e.g. el hombre guapo, el sol amarillo).
No hubo diferencia entre los pacientes que tomaron el placebo y los testigos.There was no difference between the patients who took the placebo and the controls.
declaró un testigo del accidentea person who had witnessed the accident gave evidence;tú eres testigo de que nunca le he pegadoyou can testify to o vouch for the fact that I have never hit him;estas paredes han sido testigo de nuestro amorthese walls have witnessed o are the witness of our love;pongo al cielo por testigoas God is my witness