Where does “scribendus” come from?

scribendus (Latin) comes from Latin scrībō, from Proto-Italic skreiβō, from Proto-Indo-European skreybʰ- — to write.

scribendus (Latin): which is to be written

Definitions

Step	Language	Word	Meaning
1	Latin	scrībō	—
2	Proto-Italic	skreiβō	to carve
3	Proto-Indo-European	skreybʰ-	to write

scribendus — Etymology, Origin & Word History | Etymology Explorer