1. A sentence hiding and displaying system comprising: an image creating interface receiving an input of information on an original image, a plurality of sentences corresponding to the original image, and a language that needs to be hidden; an image creator configured to determine a sentence that needs to be hidden based on the plurality of sentences and the language that needs to be hidden, and to create on the original image an image where the sentence that needs to be hidden is hidden; a sentence display interface configured to receive an input of information on a language selected by a user; and a sentence extractor and displayer configured to parse a sentence expressed in the selected language of among sentences that need to be hidden based on the hidden image and the selected language, and to display the sentence expressed in the selected language on the original image.