El discurso del candidato fue poco convincente. Incluso sus más fieles seguidores se mostraban poco entusiasmados.The candidate's speech was unconvincing. Even his most loyal followers were unenthusiastic.
Su actuación en la película es poco convincente. Cuesta creer que su personaje esté sintiendo el dolor que dice sentir.His performance in the movie isn't very convincing. It's hard to believe that his character is feeling the pain he claims to be feeling.
El argumento de la novela es poco convincente. La estás leyendo y no puedes dejar de cuestionar todo lo que ocurre en ella.The novel's plot is implausible. You're reading it and you can't help but question everything that happens in it.