The following markup uses the default side placement for the annotation:
<ex> Login: <<Enter your name>> <\ex>
It produces:
Login: Enter your name
The following markup uses the stack parameter to accommodate a long annotation:
<ex stack> Quarterly Sales Reports <<Q1: January, February, March Q2: April, May, June Q3: July, August, September Q4: October, November, December>> <\ex>
It produces: