A control apparatus controls the display of text data which includes a speech link that can be activated by spoken command. The shape of a pointing device cursor displayed on a display is then changed by the apparatus when the pointing device cursor is located over the speech link included in displayed text data. The apparatus is arranged to output a prompt identifying speech commands that can be used to activate the speech link if the pointing device cursor is displayed on a display located over the speech link in a changed state for a predetermined time.