what would have happened if (something) had (happened)

This is a phrase that's used for imagining how things would be different if an event in the past had been different. You can use this when you wish that something had happened differently, as in the example at the top. You can also use this phrase to express happiness with the way things actually happened. For example:

I can't imagine what would have happened if I'd kept drinking like that every night.

This phrase appears in these lessons: