Select Statements

Hi,

How can I fetch values for parameters...is the select statements right....how can i use ?

select-options : s_vbeln for vbak-vbeln.

Parameters : s_vkorg(10),

s_vtweg(10),

s_spart(10).

Initialization.

start-of-selection.

select a_{vbeln a}auart a_{netwr a}waerk b_{zmeng b}zieme b_{posnr b}matnr

into table itab from vbak as a inner join vbap as b on b~vbeln =

a_{vbeln where a}vbeln in s_vbeln.

select vbeln auart netwr waerk from vbak into table itab where

vkorg = s_vkorg and

vtweg = s_vtweg.

select zmeng zieme posnr matnr from vbap into table itab where

spart = s_spart.