of no avail   (TTS發音)

useless； unsuccessful； in vain沒有用

    His sickness was treated with many medicines，but all were of no avail. 他的病已用各種藥治過，但都無效。

    Tom's practicing was of no avail. He was sick on the day of the game. 湯姆平時的練習全部泡湯了，比賽那天他病了。

    Although they tried hard， their efforts seemed to be of no avail. 雖說他們花了很大力氣，但看來還是徒勞無功。