[root@localhost ~]$ cat -n temp.txt
1 My name is Ed Chen, you can call me Eddie. Here is my profile at : Google+. I live in Taipei, Taiwan and work as a Technical Supervisor at MDS System, Taiwan.
There's only one line in the file.
If you'd like to append only 1 empty line to a file, you can do this:
[root@localhost ~]$ echo >> temp.txt
If you want 2 empty lines, you can do this:
[root@localhost ~]$ echo $'n' >> temp.txt
If you want 3 empty lines, you can do this:
[root@localhost ~]$ echo $'n'$'n' >> temp.txt
[root@localhost ~]$ cat -n temp.txt
1 My name is Ed Chen, you can call me Eddie. Here is my profile at : Google+. I live in Taipei, Taiwan and work as a Technical Supervisor at MDS System, Taiwan.
2
3
4
And so on, you can predict that there will be 9 $'n' concatenated in the command to meet 10 empty lines.