Verb/subject placement
 

Hey,

So i have seen a lot of sentences like this lately where the verb comes befor the subject

Ten cuidado, viene un coche

And I know that for certain sentences like "what did he say" it's always "¿Qué dijo él?" but I don't know why.

Is there a specific rule for this or what?

It doesn't matter much what order is used. The only 'difference' I hear is an emphasis shift. The meaning doesn't change.

Look here. It's in Spanish.

¡Gracias, Rusty! Es un buenísimo recurso.

Thanks for the link. A question the link can't answer, is one way or the other more natural for some sayings? Like the dijo expressions?

It seems much more natural to ask, "¿Qué dijo él?"
But, when you're not using the interrogative, it's more natural to say, "Él dijo."

That said, I often reverse subject and verb when using decir with a noun (instead of a pronoun). I learned to say it that way in Central America. The internet tends to agree with me.
'Dijo el profesor que' gets a lot more hits than 'el profesor dijo que'.