I persuaded him without avail.

我劝是劝过他了，但没有用。

Nicola: I've proposed to four different men without avail.

Nicola：我向四个不同的男人求过婚都没有成功。

She tried to argue herself out of the infatuation, but without avail.

她想说服自己摆脱迷恋，可是没成功。

Much to my regret that we have made repeated application for payment of this amount without avail.

我们多次去函请求结清这笔账款而无任何结果，为此我们非常遗憾。

Weapons are of no avail without the people who use them.

只有武器而没有使用它们的人，武器是空的。