Hello,
I use `debian 9`;
after removing `apt purge libreoffice*`
I'am trying to `$ sudo apt install -t stretch-backports libreoffice-writer libreoffice-impress libreoffice-calc libreoffice-kde libreoffice-style
-oxygen `,
but I get an error
```sh
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-calc : Depends: libreoffice-base-core (= 1:5.4.4-1~bpo9+1) but it is not going to be installed
Depends: libreoffice-core (= 1:5.4.4-1~bpo9+1) but it is not going to be installed
libreoffice-impress : Depends: libreoffice-core (= 1:5.4.4-1~bpo9+1) but it is not going to be installed
Depends: libreoffice-draw (= 1:5.4.4-1~bpo9+1) but it is not going to be installed
Recommends: libreoffice-avmedia-backend-gstreamer but it is not going to be installed or
libreoffice-avmedia-backend-vlc but it is not going to be installed
libreoffice-kde : Depends: libreoffice-core (= 1:5.2.7-1) but it is not going to be installed
Recommends: libreoffice-style-breeze but it is not going to be installed
libreoffice-style-oxygen : Depends: libreoffice-common (= 1:5.2.7-1) but 1:5.4.4-1~bpo9+1 is to be installed
libreoffice-writer : Depends: libreoffice-base-core (= 1:5.4.4-1~bpo9+1) but it is not going to be installed
Depends: libreoffice-core (= 1:5.4.4-1~bpo9+1) but it is not going to be installed
Recommends: libreoffice-math but it is not going to be installed
E: Unable to correct problems, you have held broken packages.
```
Can you help to fix it?