无法在Ubuntu 16.04上安装PHP 7.4，即使apache2中有Ondrej PPA库?

Question

我试图在Apache2服务器的Ubuntu 16.04上安装PHP 7.4。为了安装7.4版本，我使用了ppa:ondrej库，如下所示:

sudo apt install software-properties-common
sudo add-apt-repository ppa:ondrej/php
sudo apt update
sudo apt install -y php7.4
php -v

我得到以下错误：

Reading package lists... Done
Building dependency tree       
Reading state information... Done
E: Unable to locate package php7.4
E: Couldn't find any package by glob 'php7.4'
E: Couldn't find any package by regex 'php7.4'

我如何安装这个软件包？

Answer 1

apt search php7.4

Answer 2

应该是系统版本太老了。不维护了吧。