# apt-mark --help
apt 1.2.18 (amd64)
Usage: apt-mark [options] {auto|manual} pkg1 [pkg2 ...]
apt-mark is a simple command line interface for marking packages
as manually or automatically installed. It can also be used to
manipulate the dpkg(1) selection states of packages, and to list
all packages with or without a certain marking.
Most used commands:
auto - Mark the given packages as automatically installed
manual - Mark the given packages as manually installed
hold - Mark a package as held back
unhold - Unset a package set as held back
showauto - Print the list of automatically installed packages
showmanual - Print the list of manually installed packages
showhold - Print the list of package on hold
See apt-mark(8) for more information about the available commands.
Configuration options and syntax is detailed in apt.conf(5).
Information about how to configure sources can be found in sources.list(5).
Package and version choices can be expressed via apt_preferences(5).
Security details are available in apt-secure(8).