SQN!
Basta você utilizar begin of line na declaração de seus parâmetros e pronto! Este comando faz com que o bloco de campos entre o begin of line e o end of line, fiquem na mesma linha, bastando a você apenas informar os textos e informações de posicionamento.
REPORT ZSAPeiros.
SELECTION-SCREEN BEGIN OF BLOCK b01 WITH FRAME TITLE text-000.
SELECTION-SCREEN BEGIN OF LINE.
PARAMETERS: p_check1 AS CHECKBOX DEFAULT 'X'.
SELECTION-SCREEN COMMENT 3(10) p_campo1.
PARAMETERS: p_check2 AS CHECKBOX.
SELECTION-SCREEN COMMENT 16(8) p_campo2.
SELECTION-SCREEN END OF LINE.
SELECTION-SCREEN SKIP.
SELECTION-SCREEN BEGIN OF LINE.
PARAMETERS: p_check3 RADIOBUTTON GROUP r01 DEFAULT 'X'.
SELECTION-SCREEN COMMENT 3(10) p_campo3.
PARAMETERS: p_check4 RADIOBUTTON GROUP r01.
SELECTION-SCREEN COMMENT 16(10) p_campo4.
PARAMETERS: p_check5 RADIOBUTTON GROUP r01.
SELECTION-SCREEN COMMENT 29(10) p_campo5.
PARAMETERS: p_check6 RADIOBUTTON GROUP r01.
SELECTION-SCREEN COMMENT 42(8) p_campo6.
SELECTION-SCREEN END OF LINE.
SELECTION-SCREEN SKIP.
SELECTION-SCREEN BEGIN OF LINE.
SELECTION-SCREEN COMMENT 1(8) p_campo7.
PARAMETERS: p_check7 TYPE char10.
SELECTION-SCREEN COMMENT 25(8) p_campo8.
PARAMETERS: p_check8 TYPE char10.
SELECTION-SCREEN END OF LINE.
SELECTION-SCREEN END OF BLOCK b01.
AT SELECTION-SCREEN OUTPUT.
p_campo1 = 'Campo 01'.
p_campo2 = 'Campo 02'.
p_campo3 = 'Campo 03'.
p_campo4 = 'Campo 04'.
p_campo5 = 'Campo 05'.
p_campo6 = 'Campo 06'.
p_campo7 = 'Campo 07'.
p_campo8 = 'Campo 08'.
INITIALIZATION.
sy-title = 'SAPeiros: Campos na mesma linha'.