linux下打印井号和感叹号时使用单引号而不是双引号

错误示例和对应的报错：

printf "#!/bin/bash \n #PBS -N step7-rsem-calculate-expression1 \n"
!/bin/bash: event not found

正确示例：

printf '#!/bin/bash \n#PBS -N step7-rsem-calculate-expression1 \n'
#!/bin/bash
#PBS -N step7-rsem-calculate-expression1