我写了一个脚本，想知道我犯的错误
在ubuntu中运行，但出现了一些错误
#!/bin/bash
echo "Enter Your Name"
read name
echo "Welcome $name to cff"
done
#Run the file with bash command.
$ bash user_input.sh
echo "Enter username”
read username
echo "Enter password”
read password
if [[ ( $username == "admin" && $password == "secret" ) ]]; then
echo "valid user”
else
echo "invalid user”
fi
#Run the file with bash command.
$ bash if_with_AND.sh
file='book.txt'
while read line; do
echo $line
done < $file
#Run the file with bash command.
$ bash read_file.sh
#Run the following command to check the original content of ‘book.txt’ file.
$ cat book.txt
echo All done
这个脚本好吗，我希望它很好 我想知道如何将3个脚本链接在一起