Render ViewHelper <f:render>

<f:render partial="SomePartial" arguments="{foo: someVariable}" />

the content of the partial "SomePartial". The content of the variable {someVariable} will be available in the partial as {foo}

<f:section name="someSection">This is a section. {foo}</f:section>
<f:render section="someSection" arguments="{foo: someVariable}" />

the content of the section "someSection". The content of the variable {someVariable} will be available in the partial as {foo}

<f:section name="mySection">
    <ul>
        <f:for each="{myMenu}" as="menuItem">
            <li>
                {menuItem.text}
                <f:if condition="{menuItem.subItems}">
                    <f:render section="mySection" arguments="{myMenu: menuItem.subItems}" />
                </f:if>
            </li>
        </f:for>
    </ul>
   </f:section>
   <f:render section="mySection" arguments="{myMenu: menu}" />

<ul>
    <li>menu1
        <ul>
          <li>menu1a</li>
          <li>menu1b</li>
        </ul>
    </li>
[...]
(depending on the value of {menu})

<f:render partial="somePartial" arguments="{_all}" />

the content of the partial "somePartial".
Using the reserved keyword "_all", all available variables will be passed along to the partial

<f:render delegate="My\Special\ParsedTemplateImplementation" arguments="{_all}" />