apt install php7.4 Reading package lists... Done Building dependency tree Reading state information... Done Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required packages have not yet been created or been moved out of Incoming. The following information may help to resolve the situation: The following packages have unmet dependencies: php7.4 : Depends: libapache2-mod-php7.4 but it is not going to be installed or php7.4-fpm but it is not going to be installed or php7.4-cgi but it is not going to be installed E: Unable to correct problems, you have held broken packages.
dpkg -l | grep php7.4
ii php7.4-bcmath 7.4.5-1+ubuntu19.10.1+deb.sury.org+1 amd64 Bcmath module for PHP ii php7.4-common 7.4.5-1+ubuntu19.10.1+deb.sury.org+1 amd64 documentation, examples and common module for PHP ii php7.4-sqlite3
没有删除ppa ondrej，apt清理，更新/升级，apt install -f没有成功。