The symbol . (dot) actually means a gap between the password sequence. Each separate piece of clues tell you a little how the complete password sequence look like
Example
[ 1 2 . 1 2 3 ] the password start with 1 2 then have gap in between and end with 1 2 3
[ 1 2 . 1 2 3 the password start with 1 2 then has gap, then continue with 1 2 3, and then still has gap until the password sequence end
Example
[ 1 2 . 1 2 3 ] the password start with 1 2 then have gap in between and end with 1 2 3
[ 1 2 . 1 2 3 the password start with 1 2 then has gap, then continue with 1 2 3, and then still has gap until the password sequence end
Nazure 
VSpang 