1.1）if case test the results

#!bin/bash
read -p “请输入你的成绩：” num
if [ $num -ge 0 ] && [ $num -le 100 ];then

if [ $num -ge 80 ] && [ $num -le 100 ];then
echo “成绩优秀”
elif [ $num -ge 60 ] && [ $num -le 79 ];then
echo “成绩合格”
else
echo “成绩不合格”
fi

else
echo “请输入正确的成绩”
fi