21 Days by Blink 182
Tabbed by Mike King (mking@elknet.net)

I went through a great deal of tabs for 21 Days on the internet
and they were all terribly wrong.  Here is the corrected version.
It seems everyone heard the intro extremely wrong.  The others
were good trys though.  This is absolutely correct (with the
exception of the counting in the intro, you should be able to
figure out the timing yourself).  I also don't really see any
chorus in the song, so you could call the pre-verse the verse
and the verse the chorus.  In pre-verse 1, try to slide from B
(A-string, fret 2) to G (E-string, fret 3)

*Intro*
G:-7-----7-----7---7---7-------
D:---0-0---0-0---0---0---0-0-0-
A:-----------------------------
E:-----------------------------

G:-7-----9-----11-----12---11---9----------
D:---0-0---0-0----0-0----0----0---0-0-0-0-0
A:-----------------------------------------
E:-----------------------------------------

G:-7-----9-----11-----12---14---
D:---0-0---0-0----0-0----0----0-
A:------------------------------
E:------------------------------

G:-12-----11-----9-----11-----12-----14--
D:----0-0----0-0---0-0----0-0----0-0----0
A:---------------------------------------
E:---------------------------------------

G:-12---9---11---12-----14-----12---11---9--
D:----0---0----0----0-0----0-0----0----0---0
A:------------------------------------------
E:------------------------------------------

*Pre-Verse 1*
G:---------------------------------------------------------------------
D:---------------------------------------------------------------------
A:-5-5-5-5-5-5-5-5-5-5-5-5-5-5-5-5--0-0-0-0-0-0-0-0--2-2-2-2--/--------
E:-----------------------------------------------------------/--3-3-3-3

*Verse 1*
G:------------------------------------------------------------------
D:--------------------------7-7-7-7--5--5-5--5--5--5-5-5-5-/-4-4-4-4
A:-5-5-5-5-5-5-5-5-5-5-5-5------------------------------------------
E:------------------------------------------------------------------

*Pre-Verse 2*
G:--------------------------------------------------------------------
D:----------------------------------7-7-7-7-7-7-7-7--9-9-9-9-/-5-5-5-5
A:-5-5-5-5-5-5-5-5-5-5-5-5-5-5-5-5------------------------------------
E:--------------------------------------------------------------------

*Verse 2*
G:--------------------------------------------------------------------------
D:------------------5----5----5----5----5-----------------------------------
A:-7-7-7-7-7-7-7-7-------------------------5-5-5-5-5-5-5-5-5-5-5-5-5-5-5-5--
E:-------------------------------------------------------------------------7

*Interlude*
G:--------------------------------------------------------------------
D:--------------------------------------------------------------------
A:-5-5-5-5-5-5-5-5-5-5-5-5-5-5-5-5------------------------------------
E:----------------------------------5-5-5-5-5-5-5-5--7-7-7-7-/-3-3-3-3

*Ending*
G:--------------------------------------------------------------------------------------------------
D:--------------------------------------------------------------------------------------------------
A:----------------------------------5-5-5-5-5-5-5-5-5-5-5-5-5-5-5-5---------------------------------
E:-3-3-3-3-3-3-3-3-3-3-3-3-3-3-3-3-----------------------------------5-5-5-5-5-5-5-5-5-5-5-5-5-5-5-5

G:---------------------------------
D:---------------------------------
A:------------------3-3-3-3-3-3-3-3
E:-7-7-7-7-7-7-7-7-----------------