One common typing error that you should watch out for
is forgetting to end a superscript or subscript
with a blank or other delimiter (like tilde).
For instance, you often see output like
because there wasn't a space left between the 2 and the ).
What we really wanted, of course, was
Modify "Example" to produce this output, then type "ready".
#once neqn Ref | nroff >X1 &
#once neqn message Ref | nroff -T$term %s/tinyms -