在过去的几周里，我一定在我的 Ubuntu 20.04 LTS 机器上弄乱了我的包：
# apt-get install libreoffice
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:
libreoffice : Depends: libreoffice-base but it is not going to be installed
Depends: libreoffice-calc but it is not going to be installed
Depends: libreoffice-core (= 1:7.2.3~rc2-0ubuntu0.18.04.1~lo1) but it is not going to be installed
Depends: libreoffice-draw but it is not going to be installed
Depends: libreoffice-impress but it is not going to be installed
Depends: libreoffice-math but it is not going to be installed
Depends: libreoffice-report-builder-bin but it is not going to be installed
Depends: libreoffice-writer but it is not going to be installed
Depends: python3-uno (>= 4.4.0~beta2) but it is not going to be installed
Recommends: libreoffice-gnome but it is not going to be installed or
libreoffice-plasma but it is not going to be installed
Recommends: libreoffice-nlpsolver but it is not going to be installed
Recommends: libreoffice-report-builder but it is not going to be installed
Recommends: libreoffice-script-provider-bsh but it is not going to be installed
Recommends: libreoffice-script-provider-js but it is not going to be installed
Recommends: libreoffice-script-provider-python but it is not going to be installed
Recommends: libreoffice-sdbc-mysql but it is not going to be installed
Recommends: libreoffice-sdbc-postgresql but it is not going to be installed
Recommends: libreoffice-wiki-publisher but it is not going to be installed
Recommends: libreoffice-java-common (>= 1:7.2.3~rc2~) but it is not going to be installed
E: Unable to correct problems, you have held broken packages.
我从哪说起呢？有人可以建议一些步骤来修复那些损坏的包裹吗？谢谢！
更新
apt-get 更新的输出：
# apt-get update
Hit:1 http://archive.canonical.com/ubuntu focal InRelease
Hit:2 http://ppa.launchpad.net/libreoffice/ppa/ubuntu bionic InRelease
Get:3 http://security.ubuntu.com/ubuntu focal-security InRelease [114 kB]
Hit:4 http://download.virtualbox.org/virtualbox/debian focal InRelease
Hit:5 http://fr.archive.ubuntu.com/ubuntu focal InRelease
Ign:6 http://linux.dropbox.com/ubuntu disco InRelease
Hit:7 http://packages.microsoft.com/repos/code stable InRelease
Get:8 http://fr.archive.ubuntu.com/ubuntu focal-updates InRelease [114 kB]
Hit:9 http://linux.dropbox.com/ubuntu disco Release
Hit:10 http://ppa.launchpad.net/taskcoach-developers/ppa/ubuntu bionic InRelease
Hit:11 https://updates.signal.org/desktop/apt xenial InRelease
Hit:12 https://linux.teamviewer.com/deb stable InRelease
Hit:13 https://brave-browser-apt-release.s3.brave.com stable InRelease
Hit:14 https://packages.microsoft.com/repos/ms-teams stable InRelease
Hit:15 https://repo.skype.com/deb stable InRelease
Get:16 http://fr.archive.ubuntu.com/ubuntu focal-backports InRelease [108 kB]
Hit:18 https://packagecloud.io/slacktechnologies/slack/debian jessie InRelease
Get:19 http://security.ubuntu.com/ubuntu focal-security/main amd64 DEP-11 Metadata [35,7 kB]
Get:20 http://security.ubuntu.com/ubuntu focal-security/universe amd64 DEP-11 Metadata [64,7 kB]
Get:21 http://security.ubuntu.com/ubuntu focal-security/multiverse amd64 DEP-11 Metadata [2 464 B]
Get:22 http://fr.archive.ubuntu.com/ubuntu focal-updates/main amd64 DEP-11 Metadata [278 kB]
Get:23 http://fr.archive.ubuntu.com/ubuntu focal-updates/universe amd64 DEP-11 Metadata [362 kB]
Get:24 http://fr.archive.ubuntu.com/ubuntu focal-updates/multiverse amd64 DEP-11 Metadata [940 B]
Get:25 http://fr.archive.ubuntu.com/ubuntu focal-backports/main amd64 DEP-11 Metadata [7 968 B]
Get:26 http://fr.archive.ubuntu.com/ubuntu focal-backports/universe amd64 DEP-11 Metadata [11,3 kB]
Fetched 1 098 kB in 5s (235 kB/s)
Reading package lists... Done
aptitude -f install libreoffice 的输出：
# aptitude -f install libreoffice
The following NEW packages will be installed:
coinor-libcbc3{a} coinor-libcgl1{a} coinor-libclp1{a} coinor-libcoinmp1v5{a} coinor-libcoinutils3v5{a} coinor-libosi1v5{a} firebird3.0-common{a} firebird3.0-common-doc{a} firebird3.0-server-core{a}
firebird3.0-utils{a} fonts-crosextra-caladea{a} fonts-crosextra-carlito{a} fonts-linuxlibertine{a} fonts-noto-core{a} fonts-noto-extra{a} fonts-noto-ui-core{a} fonts-sil-gentium{a}
fonts-sil-gentium-basic{a} gstreamer1.0-gtk3{a} libblas3{a} libbsh-java{a} libclucene-contribs1v5{a} libclucene-core1v5{a} libcolamd2{a} libexttextcat-2.0-0{a} libexttextcat-data{a} libfbclient2{a}
libgfortran5{a} libhsqldb1.8.0-java{a} libib-util{a} liblangtag-common{a} liblangtag1{a} liblapack3{a} liblibreoffice-java{a} libmhash2{a} libmythes-1.2-0{a} libpq5{a} libraptor2-0{a} librasqal3{a}
librdf0{a} libreoffice libreoffice-base{a} libreoffice-base-core{ab} libreoffice-base-drivers{a} libreoffice-calc{ab} libreoffice-common{a} libreoffice-core{ab} libreoffice-draw{ab} libreoffice-gnome{a}
libreoffice-gtk3{a} libreoffice-impress{a} libreoffice-java-common{a} libreoffice-math{a} libreoffice-nlpsolver{a} libreoffice-report-builder{a} libreoffice-report-builder-bin{a}
libreoffice-script-provider-bsh{a} libreoffice-script-provider-js{a} libreoffice-script-provider-python{a} libreoffice-sdbc-firebird{a} libreoffice-sdbc-hsqldb{a} libreoffice-sdbc-mysql{ab}
libreoffice-sdbc-postgresql{a} libreoffice-style-colibre{a} libreoffice-style-elementary{a} libreoffice-style-yaru{a} libreoffice-wiki-publisher{a} libreoffice-writer{ab} libsuitesparseconfig5{a}
libtommath1{a} libuno-cppu3{a} libuno-cppuhelpergcc3-3{a} libuno-purpenvhelpergcc3-3{a} libuno-sal3{a} libuno-salhelpergcc3-3{a} libunoloader-java{a} libyajl2{a} lp-solve{a} python3-uno{ab}
uno-libs-private{a} ure{ab} ure-java{a}
0 packages upgraded, 82 newly installed, 0 to remove and 0 not upgraded.
Need to get 217 MB of archives. After unpacking 808 MB will be used.
The following packages have unmet dependencies:
libreoffice-sdbc-mysql : Depends: libmysqlclient20 (>= 5.7.11) which is a virtual package and is not provided by any available package
libreoffice-core : Depends: libboost-date-time1.65.1 which is a virtual package and is not provided by any available package
Depends: libboost-filesystem1.65.1 which is a virtual package and is not provided by any available package
Depends: libboost-iostreams1.65.1 which is a virtual package and is not provided by any available package
Depends: libboost-locale1.65.1 which is a virtual package and is not provided by any available package
Depends: libboost-system1.65.1 which is a virtual package and is not provided by any available package
Depends: libhunspell-1.6-0 which is a virtual package and is not provided by any available package
Depends: libicu60 (>= 60.1-1~) which is a virtual package and is not provided by any available package
Depends: libpoppler73 (>= 0.62.0) which is a virtual package and is not provided by any available package
python3-uno : Depends: python3 (< 3.7) but 3.8.2-0ubuntu2 is installed
Depends: python3.6 which is a virtual package and is not provided by any available package
Depends: libpython3.6 (>= 3.6.5) which is a virtual package and is not provided by any available package
libreoffice-base-core : Depends: libboost-date-time1.65.1 which is a virtual package and is not provided by any available package
ure : Depends: libicu60 (>= 60.1-1~) which is a virtual package and is not provided by any available package
libreoffice-writer : Depends: libicu60 (>= 60.1-1~) which is a virtual package and is not provided by any available package
libreoffice-calc : Depends: libicu60 (>= 60.1-1~) which is a virtual package and is not provided by any available package
libreoffice-draw : Depends: libicu60 (>= 60.1-1~) which is a virtual package and is not provided by any available package
The following actions will resolve these dependencies:
Keep the following packages at their current version:
1) liblibreoffice-java [Not Installed]
2) libreoffice [Not Installed]
3) libreoffice-base [Not Installed]
4) libreoffice-base-core [Not Installed]
5) libreoffice-base-drivers [Not Installed]
6) libreoffice-calc [Not Installed]
7) libreoffice-common [Not Installed]
8) libreoffice-core [Not Installed]
9) libreoffice-draw [Not Installed]
10) libreoffice-gnome [Not Installed]
11) libreoffice-gtk3 [Not Installed]
12) libreoffice-impress [Not Installed]
13) libreoffice-java-common [Not Installed]
14) libreoffice-math [Not Installed]
15) libreoffice-nlpsolver [Not Installed]
16) libreoffice-report-builder [Not Installed]
17) libreoffice-report-builder-bin [Not Installed]
18) libreoffice-script-provider-bsh [Not Installed]
19) libreoffice-script-provider-js [Not Installed]
20) libreoffice-script-provider-python [Not Installed]
21) libreoffice-sdbc-firebird [Not Installed]
22) libreoffice-sdbc-hsqldb [Not Installed]
23) libreoffice-sdbc-mysql [Not Installed]
24) libreoffice-sdbc-postgresql [Not Installed]
25) libreoffice-wiki-publisher [Not Installed]
26) libreoffice-writer [Not Installed]
27) python3-uno [Not Installed]
28) ure [Not Installed]
29) ure-java [Not Installed]
Leave the following dependencies unresolved:
30) libreoffice-base-drivers recommends libreoffice-sdbc-hsqldb
31) libreoffice-common recommends python3-uno (>= 4.4.0~beta2)
32) libreoffice-style-colibre recommends libreoffice-common
33) libreoffice-style-elementary recommends libreoffice-common
34) libreoffice-style-yaru recommends libreoffice-common
35) libreoffice-writer recommends libreoffice-math
Accept this solution? [Y/n/q/?]
当我接受解决方案时，什么都没有安装。当我接受任何其他解决方案（提出了许多解决方案）时，什么都没有安装。
我可能在尝试安装编译 linphone 所需的库时造成了这种混乱。我下载了 linphone 源代码，其中有一些未安装的软件包的依赖项，其中有几个是非标准的。可悲的是，我忘记了我到底做了什么......
最后但同样重要的是，apt policy libreoffice 的输出：
# apt policy libreoffice
libreoffice:
Installed: (none)
Candidate: 1:7.2.3~rc2-0ubuntu0.18.04.1~lo1
Version table:
1:7.2.3~rc2-0ubuntu0.18.04.1~lo1 500
500 http://ppa.launchpad.net/libreoffice/ppa/ubuntu bionic/main amd64 Packages
1:7.1.7-0ubuntu0.21.04.1~bpo20.04.1 100
100 http://fr.archive.ubuntu.com/ubuntu focal-backports/universe amd64 Packages
1:6.4.7-0ubuntu0.20.04.2 500
500 http://fr.archive.ubuntu.com/ubuntu focal-updates/universe amd64 Packages
500 http://security.ubuntu.com/ubuntu focal-security/universe amd64 Packages
1:6.4.2-0ubuntu3 500
500 http://fr.archive.ubuntu.com/ubuntu focal/universe amd64 Packages
（总结评论）
尝试安装 libreoffice 时遇到的错误是由于
focal系统引用了bioniclibreoffice ppa。完全删除 libreoffice、删除 ppa 并重新安装 libreoffice 是成功的，尽管最终结果是 libreoffice 的版本比以前安装的要旧。
系统上还有其他非
focalppas 目前没有破坏软件包系统，但可能应该在未来进行调查，如果可能的话，着眼于用focal版本替换它们。