Keywords: sale, sell
As a Noun
The letting of someone have something in return for money. English = sale.
As a Verb or Adjective
To let someone have something in return for money. English = sell.
When this sign is rapidly repeated it is often associated with a nominal (noun) meaning (i.e., the sign names an activity) like "selling" (e.g., "Selling all the goods in the shop took months.") However, this alone does not make it a noun as it could also still be used as a verb to mean "to sell again and again/over time" or "to sell habitually" (e.g., "He is selling flowers at the market this Friday as usual.") Usually it is the other signs in the sentence and the context in which it is made that tells you if a sign is to be understood as a noun or a verb.