Mixed conditionals

We can mix the second and third conditionals:

if + 2nd conditional | 3rd conditional

This type of mixed conditional expresses a general condition with an imaginary result in the past:

If I spoke better English, I could have got the job. (I don't speak English well enough, so I didn't get the job)
If you were smarter, you wouldn't have borrowed money in the first place. (you are not smart; that's why you borrowed money)

if + 3rd conditional | 2nd conditional

This type of mixed conditional expresses a hypothetical condition in the past with an imaginary result in the present:

If we had followed the sign, we wouldn't be lost now. (we didn't follow the sign, and now we are lost)
If you had drunk less last night, you wouldn't have a hangover. (you drank too much last night; that's why you have a hangover now)