Translation of "Faltered" in French

His career had faltered.

Sa carrière vacillait.

In the end, he also faltered in the face of great adversity.

Finalement, il a également vacillé face à une grande adversité.

I was going to ask her out, but at the last moment my courage faltered.

J'allais lui demander de sortir avec moi, mais au dernier moment, mon courage a vacillé.