SectionExample.xaml

<!-- <SnippetSectionExampleWholePage> -->
  <FlowDocument xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
    <!-- By default, Section applies no formatting to elements contained
         within it. However, in this example, the section has a Background
         property value of "Red", therefore, the three paragraphs (the block)  
         inside the section also have a red background. -->
    <Section Background="Red">
      <Paragraph>
        Paragraph 1
      </Paragraph>
      <Paragraph>
        Paragraph 2
      </Paragraph>
      <Paragraph>
        Paragraph 3
      </Paragraph>
    </Section>
  </FlowDocument>
<!-- </SnippetSectionExampleWholePage> -->