Change ubuntu default shell to bash

Found out that the C-style for loop does not work in ubuntu shell. After a few google search, answer is at below:
C-style for loop on works In bash (since version 2.04)
The sh command in /bin/sh is a symbolic link to /bin/dash:


steven@steven-laptop:/bin$ ls -l sh
lrwxrwxrwx 1 root root 4 2010-05-03 06:48 sh -> dash

Use 

$sudo ln -sf /bin/bash /bin/sh

to replace

To change the login shell, use the command $chsh