She found him sleeping heavily, and all her efforts to awaken him were of no avail.

她发现他睡得很沉，她想唤醒他的一切努力都无济于事。

youdao

Now it's done, regrets are of no avail.; It's no use crying over spilt milk.

事已如此， 后悔也是枉然。

《新英汉大辞典》

The advice we got was of no avail.

我们得到的这个建议根本没用。

youdao

Birmingham immediately produced a spell of pressure to no avail, while Pompey grew in confidence and authority.

BBC: Birmingham 0-2 Portsmouth

Businessman Pong Salud, another guest, takes me aside and tells me that some friends gave Estrada three sets of golf clubs to no avail.

CNN: DAYS OF THEIR LIVES

If she had been diagnosed with pancreatic cancer, fought through rounds of chemo and radiation to no avail, and decided against a bone marrow transplant (which, in this hypothetical situation, which reflects the vast majority of real cases, would more likely kill her than enable a cure) she would be honored and remembered as noble, virtuous and brave.

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