If for some reason does not work bash completion in terminal (using the TAB key), look inside the file bash.bashrc. Open terminal and type:

sudo gedit /etc/bash.bashrc

At the line 31 you can find this entry.

# enable bash completion in interactive shells
#if [ -f /etc/bash_completion ] && ! shopt -oq posix; then
#    . /etc/bash_completion
#fi

Uncomment it and save file.

# enable bash completion in interactive shells
if [ -f /etc/bash_completion ] && ! shopt -oq posix; then
    . /etc/bash_completion
fi