Without written evidence, we don't have a leg to stand on.

我们没有书面证据就站不住脚。

《牛津词典》

Any lawyer will tell you, if you're cohabiting and the man leaves you, you haven't got a leg to stand on.

所有的律师都会告诉你说，如果和你同居的男人离开了你，你没有权利要求经济补偿。

《柯林斯英汉双解大词典》

Charlie's life dream was to become a soldier, but he would never be able to because of his leg condition he couldn't stand on his right leg.

查理的人生梦想是成为一名士兵，但因为他的腿部状况——他无法以右腿站立，他永远也无法成为一名士兵了。

youdao

The birds also likely alternate which leg they stand on to avoid one leg becoming too cold.

BBC: Earth News - Why flamingoes stand on one leg

In short, the birds stand on one leg to conserve body heat.

BBC: Earth News - Why flamingoes stand on one leg

Instead officers say they're still checking drivers by getting them to do things like stand on one leg and walk in a straight line.

BBC: Newsbeat - Health - Drug-driving tests not ready