Select distinct cust.city 
From YRB_customer cust 
left join YRB_purchase p on cust.cid =p.cid
left join YRB_book b on p.title=b.title and b.language = 'English'
Where b.title is null

create table YRB_customer(cid int identity(1,1),city varchar(255))
create table YRB_purchase(pid int identity(1,1),cid int,title varchar(255))
create table YRB_book(bid int identity(1,1),title varchar(255),language varchar(255))

insert YRB_customer (city)
select 'Hamburg' union all
select 'London' union all
select 'New York'

insert YRB_purchase (cid,title)
select 1,'a title' union all
select 2,'another title'

insert YRB_book (title,language)
select 'a title','German' union all
select 'another title','English'

Select distinct cust.city 
From YRB_customer cust 
left join YRB_purchase p on cust.cid =p.cid
left join YRB_book b on p.title=b.title and b.language = 'English'
Where b.title is null

drop table YRB_customer
drop table YRB_purchase
drop table YRB_book