"The plate is under the bread."

Translation: Patella est sub pane.

[KimberleyL3907]

Can someone help me with pane vs panis?

[GaelicGirl2]

Here you can find the full declension.

https://en.m.wiktionary.org/wiki/panis

[cforsyte]

It's an ablative form of the word 'panis'. Specifically, ablative of means - this case was (very) superficially covered in previous lessons.