Some pages hide content unless "Read more" is clicked
What you're probably looking at is a &quot;View&quot;. This view is probably showing a list of &quot;Content&quot; (nodes).
Now each node is probably being set to render in &quot;Teaser&quot; view mode. But since some of your node types (article for example) doesn't have a &quot;teaser&quot; view mode configured, it shows the &quot;Full&quot; (or &quot;Default&quot;) view mode, which renders the &quot;whole&quot; thing.
What you need to do is find the View Mode that your content listing View is using, the Node Type of the content that's showing up as Full, (for example 'Basic Page'), then go to:
Structure &gt; Content Types &gt; [Content Type you want to configure] &gt; Manage Display
And configure the view mode that your View is using to display the Read More link, show the body text as &quot;Summary or Trimmed&quot; etc.