title: trying to use owncloud but it says some php modules not installed
body: <p>I get this error when trying to enter to <a href="http://localhost/index.php" rel="nofollow noreferrer">http://localhost/index.php</a> <br></p>
  
  <pre><code>PHP module zip not installed.
  
  Please ask your server administrator to install the module.
  PHP module dom not installed.
  
  Please ask your server administrator to install the module.
  PHP module XMLWriter not installed.
  
  Please ask your server administrator to install the module.
  PHP module XMLReader not installed.
  
  Please ask your server administrator to install the module.
  PHP module intl not installed.
  
  Please ask your server administrator to install the module.
  PHP module libxml not installed.
  
  Please ask your server administrator to install the module.
  PHP module mb multibyte not installed.
  
  Please ask your server administrator to install the module.
  PHP module GD not installed.
  
  Please ask your server administrator to install the module.
  PHP module SimpleXML not installed.
  
  Please ask your server administrator to install the module.
  PHP module cURL not installed.
  
  Please ask your server administrator to install the module.
  PHP modules have been installed, but they are still listed as missing?
  
  Please ask your server administrator to restart the web server.
  </code></pre>
  
  <p>where the owncloud is installed, I tried this command:</p>
  
  <pre><code>apt-get install -y apache2 mariadb-server libapache2-mod-php7.0     openssl php-imagick php7.0-common php7.0-curl php7.0-gd     php7.0-imap php7.0-intl php7.0-json php7.0-ldap php7.0-mbstring     php7.0-mcrypt php7.0-mysql php7.0-pgsql php-smbclient php-ssh2     php7.0-sqlite3 php7.0-xml php7.0-zip
  </code></pre>
  
  <p>but it gave me some strange error: </p>
  
  <pre><code>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:
  mariadb-server : Depends: mariadb-server-10.1 (&gt;= 1:10.1.34-0ubuntu0.18.04.1) but it is not going to be installed
  E: Unable to correct problems, you have held broken packages.
  </code></pre>
  
  <p>I have no idea what to do... I searched all the internet and didn't find an answer...</p>