printf "Hello, Shell\n"

#!/bin/bash

printf "%d %s \n" 1 "abc"
# 单引号和双引号一样
printf '%d %s \n' 2 "bcd"
# 即使不使用引号也一样
printf %s cde
# 多余的参数仍然遵循现有格式
printf %s abc def

printf "%s\n" abc def
# 未设置参数 %s 被NULL代替  %d被0代替
printf "%s and %d \n"
# 参数传递错误 
printf "The first program always prints '%s, %d' \n" "Hello" "Shell"

echo "打印是内容"        //输出内容到stdou 使用双引号""
read PERSON             //从stdin获取输入并赋值给PERSON变量
echo "Hello, $PERSON"   //输出内容,同时输出PERSON变量的值

your_name="yutiya"
echo $your_name
echo ${your_name}

for skill in Ada Coffe Action Java 
do
    echo "I am good at ${skill}Script"
done