英汉词典

1. 毫无用处;没效果
    If you do something to no avail or to little avail, what you do fails to achieve what you want.

    e.g. His efforts were to no avail...
           他徒劳无功。
    e.g. I apologized repeatedly, but to little avail.
           我一再道歉，但丝毫没有奏效。

2. 接受（提议）；利用（机会）
    If you avail yourself of an offer or an opportunity, you accept the offer or make use of the opportunity.

avail的解释

    e.g. Guests should feel at liberty to avail themselves of your facilities.
           宾客们应该可以随意使用你们的各种设施。