Trying to help him to improve his pronunciation is a lost cause.

想帮他纠正发音，肯定没什么用。

It recks little to talk of that now.

现在再谈件也没什么用了。

She never raised a hand against her daughter because she didn’t believe in hitting children.

她从不威胁要打自己的女儿，因为她觉得体罚子没什么用。

We’ve economised as much as possible,but to little great avail,since we still owe a lot of money.

我们尽可能节俭,但没什么用,因为我们仍然欠了债。