PRINV CLR A
MOVC A,@A+DPTR
JZ F_PRV
JNB TI,$
CLR TI
MOV SBUF,A
INC DPTR
LJMP PRINV
F_PRV RET
...

ORG Months
DW MEN1,MEN2,MEN3,MEN4,MEN5,MEN6,MEN7,MEN8,MEN9,MEN10,MEN11,MEN12
MEN1 DB 'January',0
MEN2 DB 'February',0
MEN3 DB 'March',0
MEN4 DB 'April',0
MEN5 DB 'May',0
MEN6 DB 'Jun',0
MEN7 DB 'July',0
MEN8 DB 'Agoust',0
MEN9 DB 'September',0
MEN10 DB 'October',0
MEN11 DB 'November',0
MEN12 DB 'December',0

You must set dptr to months+no_month*2 (no_month =[0..11]) ans call the routine.