If there are more tenacious spots to clean off, you can use a wet rag to rub them clean.

如果有顽固污渍的地方需要清理，你可以用块湿抹布擦干净。

Did you clean off the clay?

把土清理干净了吗？

Clean off your counters.

清理柜台。

I hope these black marks will clean off.

我希望这些黑斑点能除掉。

Clean off your desk.

把你的书桌擦干净。