Learn Turkish: Şoför bize bakmıyordu, iyi ki kornaya bastın! - The driver wasn't looking at us, fortunately you honked the horn!

İyi ki (fortunately / it's a good thing that) is very straightforward in Turkish. It simply comes before a regular, conjugated verb (a finite verb). It doesn't require any special mood or conditional tense. Here, it just uses the standard definite past tense: iyi ki bastın (it is a good thing that you pressed).

Why does bakmıyordu have both -yor and -du suffixes?

This forms the past continuous tense. The -yor suffix makes the action continuous, and the -du suffix puts it in the past. Together with the negative -mı, bakmıyordu translates perfectly to 'was not looking.' It sets the ongoing background scene for the sudden action of honking.

Why does the word for horn take the dative case ending in kornaya?

The verb basmak means 'to press' or 'to step on'. In Turkish, you direct this physical action towards the object being pressed, so it requires the dative case, which is -(y)a or -(y)e. You are literally saying that you applied pressure to the horn.

Is kornaya basmak the only way to say 'honk the horn'?