go pear-shaped真实含义是失败了，英国飞行员训练需要在空中画圆，但是经常会画成梨形，也就是训练失败了！

【例句】
We tried many times, but all went pear-shaped.
我们尝试了很多次，但都失败了。

We'd planned to go away for the weekend, but it all went pear-shaped.
我们本打算周末外出度假，但是一切都化为泡影了。