newbie to LPC2138,ask how to program assemble code.

hi.
I copy some codes from ADS and then plaster
them to keil as test.s file.when I compile them.some errors:

assembling test.s...
word.s(1): error A65: IDENTIFIER EXPECTED
word.s(5): error A116: NO CURRENT 'AREA'
word.s(7): error A116: NO CURRENT 'AREA'
word.s(8): error A116: NO CURRENT 'AREA'
word.s(9): error A116: NO CURRENT 'AREA'
word.s(10): error A116: NO CURRENT 'AREA'
word.s(12): error A116: NO CURRENT 'AREA'
word.s(13): error A116: NO CURRENT 'AREA'
word.s(14): error A116: NO CURRENT 'AREA'
word.s(15): error A116: NO CURRENT 'AREA'
word.s(16): error A116: NO CURRENT 'AREA'
word.s(18): error A116: NO CURRENT 'AREA'
word.s(19): error A116: NO CURRENT 'AREA'
word.s(20): error A116: NO CURRENT 'AREA'
word.s(21): error A116: NO CURRENT 'AREA'
word.s(25): error A9: SYNTAX ERROR
word.s(25): error A9: SYNTAX ERROR
word.s(26): error A9: SYNTAX ERROR
word.s(26): error A9: SYNTAX ERROR

WHY?I just kown how them work.there are the source codes.

 AREA ARMex, CODE, READONLY  ; name this block of code
        ENTRY                       ; mark first instruction
                                    ; to execute
start
        MOV     r0, #10             ; Set up parameters
        MOV     r1, #3
        ADD     r0, r0, r1          ; r0 = r0 + r1

stop
        MOV     r0, #0x18           ; angel_SWIreason_ReportException
        LDR     r1, =0x20026        ; ADP_Stopped_ApplicationExit
        SWI     0x123456            ; ARM semihosting SWI

        END                         ; Mark end of file