Adding text to checkbox

My code is similar to the following:

SELECTION-SCREEN BEGIN OF BLOCK out WITH FRAME TITLE text-s01.

SELECTION-SCREEN BEGIN OF LINE.

PARAMETERS: p_filchk AS CHECKBOX.

SELECTION-SCREEN COMMENT 4(17) text-s02 FOR FIELD p_filchk.

SELECTION-SCREEN POSITION POS_LOW.

PARAMETERS: p_file LIKE rlgrap-filename.

SELECTION-SCREEN END OF LINE.

SELECTION-SCREEN END OF BLOCK out.

Problem: I want to add text corresponding to the checkbox created(p_filchk). I tried with "Go To->Text Elements -> Selection Text" and gave text for p_filchk, but it still does not display on the screen. Could anyone please tell me how to go about it?