How to print multiple spaces in my document with XSLT

["Collin" <collin@seu.edu.cn>]

HI, all:
    I use XSLT to transform my XML document into a HTML document. I 've done every effort to have multiple spaces be printed in my browser, but I failed again and again.
    If I used   in XSLT, it would say that   is an undefined entity. 
    If I used  , it would print a space. 
    And if I used     , then it would print only one space.
    I think I must have missed something with XSLT. 
    Who can tell me how to solve it?
    Thank you.
Collin