stored procedures in sql server 2008

thanks,
this is my SP for the need i mention above , the table name to be get dynamically

create procedure SP_M
(
@proc nvarchar(50),
@vc nvarchar(255)
)
as
begin

declare @TABLENAME varchar(50)
declare @TABLENAM_IDENTITY nvarchar(50)
declare @prtable nvarchar(50)
declare @sectable nvarchar(50)

DECLARE @curs CURSOR
SET @curs = CURSOR FOR
SELECT TBL_R_ID,TBL_IDENTITY
FROM PR_TBL_IDENTITY WHERE PR_R_ID=@proc

OPEN @curs
FETCH NEXT
from @curs into @TABLENAME,@TABLENAM_IDENTITY

WHILE @@FETCH_STATUS = 0
BEGIN

PRINT @TABLENAME ---- t1 and t2, t1 has some set of datas, t2 has some set of datas
PRINT @TABLENAM_IDENTITY --- t1 is primary, t2 is secondary

IF @TABLENAM_IDENTITY='PRIMARY'
begin

set @prtable= 't'+@TABLENAME+'_V' --table 1

exec('select I_ID from'+ @prtable+'where VAL='+@vc)

end
----- i dont know what to do here to achieve my need @prtable for secondary

IF @TABLENAM_IDENTITY='secondary'
BEGIN
set @sectable='JITS_'+@TABLENAME+'_VALUE' -- table 2

exec('select C_N,C_V from'+@sectable+' where I_L_ID
in(select I_ID from'+ @prtable )

END

FETCH NEXT
FROM @curs INTO @TABLENAME,@TABLENAM_IDENTITY
END
CLOSE @curs
DEALLOCATE @curs
end

pls guide me
thnks in advance....