11. The electronic device as claimed in claim 3 , wherein, in a fourth mode, the input rule table comprises a Japanese input rule table, and the text input interface has a Japanese default interface when the text input interface operates as a Japanese interface, wherein the first display region is arranged to display a space key and an enter key in the Japanese default interface, and the second display region is arranged to display a first set of a plurality of Japanese consonants in the Japanese default interface.
11. The electronic device as claimed in claim 3 , wherein, in a fourth mode, the input rule table comprises a Japanese input rule table, and the text input interface has a Japanese default interface when the text input interface operates as a Japanese interface, wherein the first display region is arranged to display a space key and an enter key in the Japanese default interface, and the second display region is arranged to display a first set of a plurality of Japanese consonants in the Japanese default interface. 12. The electronic device as claimed in claim 11 , wherein the first display region has at least three of the display blocks, and the processor enables the display blocks of the first display region to be transparent except for the space key and the enter key, thereby changing the ratio of the interface area and the predetermined display area of the display region.