Task: Sentence Expansion
Input (English): The idiom " pig in a poke " is used to describe something which is purchased without the buyer being aware of its true nature or value .
Output (English): The English colloquialisms such as " turn out to be a pig in a poke " or " buy a pig in a poke " mean that something is sold or bought without the buyer knowing its true nature or value , especially when buying without inspecting the item beforehand .