avail

1. PHRASE If you do something to no avail or to little avail, what you do fails to achieve what you want. 徒勞[書麪]

His efforts were to no avail. 他的努力是徒勞的。

2. V-T If you avail yourself of an offer or an opportunity, you accept the offer or make use of the opportunity. 利用[正式]

Guests should feel at liberty to avail themselves of your facilities. 客人們應可以隨意使用你們的設施。