我安装了全新的 Ubuntu 16。我试图删除一些预装的应用程序，例如 thundermail，以释放一些空间（我遇到了空间问题）。我以为应用程序已成功删除，但我发现它们都还在那里，所以我再次删除，然后关闭软件和更新中心，然后重新打开它，我尝试删除的应用程序并没有被删除。
我该如何解决这个问题？
抱歉我的英语不好:)
编辑：
这是命令 sudo apt-get purge thunderbird 的输出：
The following packages were automatically installed and are no longer required:
libexo-1-0 libexo-common libexo-helpers libunique-1.0-0 libxfce4ui-1-0
libxfce4ui-common libxfce4util-bin libxfce4util-common libxfce4util7
libxfconf-0-2 linux-headers-4.15.0-45 linux-headers-4.15.0-45-generic
linux-image-4.15.0-45-generic linux-modules-4.15.0-45-generic
linux-modules-extra-4.15.0-45-generic linux-modules-extra-4.15.0-66-generic
xfconf
Use 'sudo apt autoremove' to remove them.
The following packages will be REMOVED:
thunderbird*
0 upgraded, 0 newly installed, 1 to remove and 94 not upgraded.
After this operation, 0 B of additional disk space will be used.
Do you want to continue? [Y/n] y
(Reading database ... 310378 files and directories currently installed.)
Removing thunderbird (1:60.9.0+build1-0ubuntu0.16.04.2) ...
Purging configuration files for thunderbird (1:60.9.0+build1-0ubuntu0.16.04.2) ...