alias not working

[Mike McClain]

I have a non-standard calender file with entries like this:

May 5 '23       Fri 1900    next TASCA dance

May 6 '23       Sat 1800    Cherokee Co. barn dance, CC Expo

I have an alias 'mo' defined as so:

alias mo='m=$(command date "+%b");
    echo; echo Today is $(command date "+%a %-d %b. %Y %-k:%M");
    if [ -z "$1" ]; then
        egrep "^$m" calendar;
    else
        egrep "^$1" calendar;
    fi'

If I just execute 'mo' it works fine showing me all this month's
entries but if I ask for next month's entries I get a syntax error.

mike@RPI4b2:~>  mo May

Today is Wed 26 Apr. 2023 12:08
-bash: syntax error near unexpected token May'

Help would be appreciated.
Thanks,
Mike
--
If a 'train station' is where a train stops, what's a 'workstation'?