我在公园散步时突然想到了解决办法。

The solution ___hit me while I was walking in the park.

我正凝视着窗外，突然意识到了真相。

I was staring out the window when the realisation ___hit me.

当我看着那张旧照片时，一阵回忆突然涌上心头。

As I looked at the old photograph, a flood of memories suddenly ___hit me.