inser variable into the tag

[lontana]

Hi all,
I am new in Javascript world so this question might be for some very simple but still I could not find a solution for it by seraching the web.
I have a variable:
var myvar="mystring";
that I want to print together with a html tag:
("<span class=\"myclass\">"document.write(myvar)"</span>")
Could someone help me?
Thanks

[PeejAvery]

document.write('<span class="myclass">' + myvar + '</span>');