Effacez le tableau noir.
Un chiffon (a rag) or une brosse (a brush) or une éponge (a sponge) can be used to erase chalk on the blackboard.
"Blackboard" in Chinese is 黑板 (Hēi băn)
le tableau noir
le tableau, le tableau noir
Borrador
pizarra (blackboard)
The Board
"Pizarra" is "blackboard" in English
loo-ach (לוח)
effacer.
The word for chalk is "craie" and a chalkboard is "tableau noir" (blackboard).
If you mean pizarra, that means "blackboard" or "chalkboard" in English.