I have tried hard for her, but all to no purpose.

他想尽一切办法去实现他的目标。

youdao

He tried to find out the cause, but all to no purpose.

他试图找出原因，但是全无结果。

youdao

They read deep and learned books to him, and then the lightest and most trifling that could be found, but all to no purpose.

人们念些深奥的书给他听，或念些世上最轻松的读物给他听，但这对他的病也没有什么好处。

youdao

But the result is an unwieldy hydra of a book that, having made its point early on, lashes out in all directions to no clear purpose.

ECONOMIST: America and Israel

Direct contacts with the Iraqi regime, if they are to be had at all, should be for no other purpose than to convey this message.

CENTERFORSECURITYPOLICY: Center for Security Policy | ��Fatal Attraction��? US Interests In Gulf, Beyond Jeopardized By Bush Personal Diplomacy Obsession

That is, here is a glaring waste of electric power, fully lighting a business through all its nighttime inactivity, every single night, for no purpose at all except to advertise its presence to almost empty midnight streets.

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