deb http://mirrors.aliyun.com/ubuntu/ focal main restricted deb http://mirrors.aliyun.com/ubuntu/ focal-updates main restricted deb http://mirrors.aliyun.com/ubuntu/ focal universe deb http://mirrors.aliyun.com/ubuntu/ focal-updates universe deb http://mirrors.aliyun.com/ubuntu/ focal multiverse deb http://mirrors.aliyun.com/ubuntu/ focal-updates multiverse deb http://mirrors.aliyun.com/ubuntu/ focal-backports main restricted universe multiverse deb http://mirrors.aliyun.com/ubuntu/ focal-security main restricted deb http://mirrors.aliyun.com/ubuntu/ focal-security universe deb http://mirrors.aliyun.com/ubuntu/ focal-security multiverse1.2 打开 /etc/apt/source.list文件
sudo vim /etc/apt/source.list1.3 删除文件内的所有内容：进入文件后，使用shift+g，进入到最后一行；按esc键，然后使用:1,.d即可删除所有内容。 1.4 将搜索到的阿里源粘贴在/etc/apt/source.list文件中，使用:wq保存并且退出 1.5 执行更新
sudo apt-get update2. 安装font-manager
sudo apt-get install font-manager
即可安装成功
