Using A Cursor In A Function

I'm creating a user-defined functtion, with a cursor in it.... I really do not understand the errors that I am getting when I try to run my query :

Server: Msg 444, Level 16, State 1, Procedure BusStatus_chk, Line 48
Select statements included within a function cannot return data to a client.
Server: Msg 444, Level 16, State 1, Procedure BusStatus_chk, Line 66
Select statements included within a function cannot return data to a client.
Server: Msg 444, Level 16, State 1, Procedure BusStatus_chk, Line 69
Select statements included within a function cannot return data to a client.

The Create procedure statement is as follows:

CREATE FUNCTION DBO.BusStatus_chk( @busreg as varchar(10), @wday as tinyint, @stime as smalldatetime, @endtime as smalldatetime )
RETURNS int
AS
BEGIN

DECLARE @totaltime smallint
DECLARE @cnt int
DECLARE @thisDur smallint

Set @cnt = (Select Count(*) from Bus_Status where Bus_Reg = @busreg AND week_day = @wday)

IF @cnt > 0
BEGIN
Select @thisDur = DATEDIFF(mi, @stime, @endtime);

Select @totaltime = SUM(DATEDIFF(mi, Start_time, end_time))
FROM Bus_Status
WHERE Bus_Reg=@busreg AND week_day=@wday
END;

IF @totaltime !> 0
BEGIN
Select @totaltime=0;
END;

IF @thisDur !> 0
BEGIN
Select @thisDur = 0
END;

Select @totaltime = @totaltime + @thisDur

IF @totaltime > 600
BEGIN
RETURN 0
END;

DECLARE bustimes_cur CURSOR FOR
SELECT * FROM Bus_Status
WHERE Bus_Reg=@busreg AND week_day=@wday
AND @stime BETWEEN start_time and end_time

OPEN bustimes_cur
FETCH FIRST FROM bustimes_cur
WHILE @@FETCH_STATUS = 0
BEGIN
FETCH NEXT FROM bustimes_cur
END
Select @@CURSOR_ROWS

IF @@CURSOR_ROWS > 0
BEGIN
RETURN 0
END;

CLOSE bustimes_cur
DEALLOCATE bustimes_cur

DECLARE busEndtimes_cur CURSOR FOR
SELECT * FROM Bus_Status
WHERE Bus_Reg=@busreg AND week_day=@wday
AND end_time BETWEEN @stime and @endtime

OPEN busEndtimes_cur
FETCH FIRST FROM busEndtimes_cur
WHILE @@FETCH_STATUS = 0
BEGIN
FETCH NEXT FROM busEndtimes_cur
END;

IF @@CURSOR_ROWS > 0
BEGIN
RETURN 0
END;

CLOSE busEndtimes_cur
DEALLOCATE busEndtimes_cur

RETURN 1
END
--END OF FUNCTION busStatus_chk

:confused: :confused:
PLEASE HELP!!!