If to no avail, then halt, or you will disgrace yourself and worse, lose the friendship.

如果不接受，便当停止，不要自取其辱而又失去友谊。

youdao

American negotiators were ready to withhold the tariffs if China made concessions, but to no avail.

只要中国作出一些让步，美国的协调员已经准备撤回这一关税政策，但是没有成果。

youdao

Your efforts will not come to no avail, if you can achieve something at last.

如果最后你能够有所成就， 你的努力就不会白费。

youdao

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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