Simple include
.
!!!include(a.md)!!!

*content*
.
<p><em>a content</em></p>
<p><em>content</em></p>
.


Nested includes
.
!!!include(b.md)!!!

*content*
.
<p><em>b content</em></p>
<p><em>a content</em></p>
<p><em>content</em></p>
.


includes in sub directories
.
!!!include(L1/a1.md)!!!

!!!include(L1/L2/a2.md)!!!

*content*
.
<p><em>a1 content</em></p>
<p><em>a2 content</em></p>
<p><em>content</em></p>
.


includes in sub directories. L1/L2/b2.md includes c2.md
.
!!!include(L1/L2/b2.md)!!!

*content*
.
<p><em>b2 content</em></p>
<p><em>c2 content</em></p>
<p><em>content</em></p>
.


includes in sub directories. L1/L2/d2.md includes ../../a.md, ../a1.md, ../../L1/L2/a2.md
.
!!!include(L1/L2/d2.md)!!!

*content*
.
<p><em>d2 content</em></p>
<p><em>a content</em></p>
<p><em>a1 content</em></p>
<p><em>a2 content</em></p>
<p><em>content</em></p>
.


inline includes
.
!!!include(x.md)!!!!!!include(y.md)!!!!!!include(z.md)!!!

*content*
.
<p><em>x contenty contentz content</em></p>
<p><em>content</em></p>
.