CORRECT TEXT
Make Secondary belongs the jackie and curtin users on sysuser group. But david user should not
belongs to sysuser group.

Answer:

Explanation:
1. usermod -G sysuser jackie
2. usermod -G sysuser curtin
3. Verify by reading /etc/group file
Using usermod command we can make user belongs to different group. There are two types of
group one primary and another is secondary. Primary group can be only one but user can belongs
to more than one group as secondary.
usermod -g groupname username àTo change the primary group of the user
usermod -G groupname username àTo make user belongs to secondary group.