Learn Italian: Non abbiamo ancora visto la crepa sul muro. - We haven't seen the crack on the wall yet.

In Italian, common adverbs of time like ancora (yet/still), già (already), and mai (never) are usually placed directly between the auxiliary verb (abbiamo) and the past participle (visto). While you might occasionally hear it at the end of the sentence for emphasis, placing it in the middle is the standard and most natural word order.

Could I use parete instead of muro for the word "wall" here?

Yes, but there is a subtle difference in meaning. A muro usually refers to a heavy, structural, or exterior wall (like a load-bearing brick wall). A parete typically refers to an interior partition wall dividing rooms, or just the visible inner surface of a wall. A crack on a muro sounds structurally more serious!

In English, we often say a crack is "in" the wall. Why does Italian use sul muro ("on" the wall)?

Italian conceptualizes the crack as a flaw appearing on the surface of the wall, hence su + il = sul (on the). If you said nel muro (in the wall), it would sound like something is buried deeply inside the wall's interior structure, like a water pipe or hidden wires.

What exactly does the word crepa imply, and are there other words for "crack"?