thing.tt:

I am thing.

##</code><code>##

thang.tt:

I am thang.

##</code><code>##

fred.tt:

% INCLUDE thing.tt %

% INCLUDE thang.tt %

##</code><code>##

<! -- begin fred.tt -->
<! -- begin thing.tt -->
I am thing.
<! -- end thing.tt -->
<! -- begin thang.tt -->
I am thang.
<! -- end thang.tt -->
<! -- end fred.tt -->