[Shell Script] 어떻게 풀어야 할지 감이 안오네요

cat test.sh
 
#!/bin/bash
 
export LANG=C
export LC_ALL=C
 
RUNCNT=`cat ./test | wc -l`
 
for ((RUN=1; RUN <= RUNCNT ; RUN++));
do
           PRINT_LINE=`sed -n ${RUN}p ./test`    
           WORKING_LIST=`cat ./test.list`
 
           for LIST in ${WORKING_LIST}
           do
                     MODIFI_LINE_NO=`grep -n "^${LIST}" ./test | cut -d ":" -f1`     
 
                     if [ ${RUN} -eq ${MODIFI_LINE_NO} ]
                     then
                                echo "MMM - `sed -n ${RUN}p ./test`"
                     fi
           done   
                     echo ${PRINT_LINE}
done