This is the way Alejandro plays it (Hannah plays the same chords not using a capo):
Capo 5

Intro: G D Em D

GHey, (320003@1)boy you never had much game
                 D (xx0232@1)EmThought (022000@1)I needed to upgrade
                                DSo (xx0232@1)I went and walked away way way
GNow, (320003@1)I see you've been hanging out
                 D (xx0232@1)    EmWith (022000@1)that other girl in town
                                      DLooking (xx0232@1)like a pair of clowns clowns clowns

BRIDGE:
GRemember (320003@1)all the things that you and I did first?
                               DAnd (xx0232@1)now you're doing them with her
EmRemember (022000@1)all the things that you and I did first?
                              DYou (xx0232@1)got me, got me like this
GAnd (320003@1)now you're taking her to every restaurant
                        DAnd (xx0232@1)everywhere we went, come on!
EmAnd (022000@1)now you're taking her to every restaurant
                              DYou (xx0232@1)got me, got me like this

CHORUS:
GBoy (320003@1)you can say anything you want 
                                    DI (xx0232@1)don't give a shh, no one else can have ya
EmI (022000@1)want you back I want you back
                            DWa-want (xx0232@1)you, want you back
GI (320003@1)broke it off thinking you'd be cryin'
                                    DNow (xx0232@1)I feel like shh looking at you flyin'
Em (022000@1)                            
I want you back I want you back
                            DWa-want (xx0232@1)you, want you back

G (320003@1)Please, this ain't even jealousy
                  D (xx0232@1)    EmShe (022000@1)ain't got a thing on me
                                           DTryin' (xx0232@1)to rock them ugly jeans jeans jeans
GYou (320003@1)clearly didn't think this through
                   D (xx0232@1)     EmIf (022000@1)what I've been told is true 
                                         DYou'll (xx0232@1)be crawling back like boo hoo hoo

BRIDGE:
GRemember (320003@1)all the things that you and I did first?
                               DAnd (xx0232@1)now you're doing them with her
EmRemember (022000@1)all the things that you and I did first?
                              DYou (xx0232@1)got me, got me like this
GAnd (320003@1)now you're taking her to every restaurant
                        DAnd (xx0232@1)everywhere we went, come on!
EmAnd (022000@1)now you're taking her to every restaurant
                              DYou (xx0232@1)got me, got me like this

CHORUS:
GBoy (320003@1)you can say anything you want 
                                    DI (xx0232@1)don't give a shh, no one else can have ya
EmI (022000@1)want you back I want you back
                            DWa-want (xx0232@1)you, want you back
GI (320003@1)broke it off thinking you'd be cryin'
                                    DNow (xx0232@1)I feel like shh looking at you flyin'
Em (022000@1)                            
I want you back I want you back
                            DWa-want (xx0232@1)you, want you back

G (320003@1)                    D (xx0232@1)     EmOhhh, (022000@1)I thought you'd still be mine 
                                      DWhen (xx0232@1)I kissed you goodbye uh oh uh oh
G (320003@1)                 D (xx0232@1)      EmOhhh, (022000@1)and you might be with her 
                                      DBut (xx0232@1)I still had you first uh oh uh oh

BRIDGE:
GRemember (320003@1)all the things that you and I did first?
                               DAnd (xx0232@1)now you're doing them with her
EmRemember (022000@1)all the things that you and I did first?
                              DYou (xx0232@1)got me, got me like this

CHORUS:
GBoy (320003@1)you can say anything you want 
                                    DI (xx0232@1)don't give a shh, no one else can have ya
EmI (022000@1)want you back I want you back
                            DWa-want (xx0232@1)you, want you back
GI (320003@1)broke it off thinking you'd be cryin'
                                    DNow (xx0232@1)I feel like shh looking at you flyin'
Em (022000@1)                            
I want you back I want you back
                            DWa-want (xx0232@1)you, want you back

G (320003@1)   D (xx0232@1)EmOhhh, (022000@1)I want you back
I want you back            D (xx0232@1)Wa-want you, want you back

G (320003@1)   D (xx0232@1)EmOhhh, (022000@1)I want you back
I want you back  
                          DWa-want (xx0232@1)you, want you back