A method for providing a user interface, UI, comprising: displaying a character input UI; receiving a user command for selecting a specific character (411, 511, 611, 811, 911) on the character input UI; determining an input mode between a recommended character input mode and an accent mark character input mode, based on the user command; and displaying, on an edge area of a character item that corresponds to the specific character, a first character input UI or a second character input UI according to the character input mode as determined, wherein determining the input mode comprises determining the input mode based on at least one of: a number of times the specific character is successively input within a first preset time period, a time for which the specific character is input, and characteristics of the specific character, and wherein the first character input UI comprises recommended character items (421, 422, 423, 424), each of the recommended character items comprising a predicted character to be input next to the selected character, and the second character input UI comprises accent mark character items (431, 432, 433, 434), each of the accent mark character items comprising a possible accent mark character to replace the selected character, wherein the method further comprises: when a character item corresponding to the specific character is selected within a second preset time period after displaying the first character input UI, changing the recommended character input mode to the accent mark character input mode and displaying the second character input UI, and when a character item corresponding to the specific character is selected within the second preset time period after displaying the second character input UI, changing the accent mark character input mode to the recommended character input mode and displaying the first character input UI. displaying a character input UI; receiving a user command for selecting a specific character (411, 511, 611, 811, 911) on the character input UI; determining an input mode between a recommended character input mode and an accent mark character input mode, based on the user command; and displaying, on an edge area of a character item that corresponds to the specific character, a first character input UI or a second character input UI according to the character input mode as determined, wherein determining the input mode comprises determining the input mode based on at least one of: a number of times the specific character is successively input within a first preset time period, a time for which the specific character is input, and characteristics of the specific character, and wherein the first character input UI comprises recommended character items (421, 422, 423, 424), each of the recommended character items comprising a predicted character to be input next to the selected character, and the second character input UI comprises accent mark character items (431, 432, 433, 434), each of the accent mark character items comprising a possible accent mark character to replace the selected character, wherein the method further comprises: when a character item corresponding to the specific character is selected within a second preset time period after displaying the first character input UI, changing the recommended character input mode to the accent mark character input mode and displaying the second character input UI, and when a character item corresponding to the specific character is selected within the second preset time period after displaying the second character input UI, changing the accent mark character input mode to the recommended character input mode and displaying the first character input UI. when a character item corresponding to the specific character is selected within a second preset time period after displaying the first character input UI, changing the recommended character input mode to the accent mark character input mode and displaying the second character input UI, and when a character item corresponding to the specific character is selected within the second preset time period after displaying the second character input UI, changing the accent mark character input mode to the recommended character input mode and displaying the first character input UI.