php
The quickest way should be to add a new block with PHP input format. In that block, call drupal_get_form() and output the result of that. You could do the same using a custom module.
<?php
global $user;
$type = 'nodetype';
$node = array('uid' => $user->uid, 'name' => $user->name, 'type' => $type);
print drupal_get_form($type . '_node_form', $node);
?>Forms provide a way to send user values and choices to the server. Forms are composed of text controls, selection lists, radio buttons, checkboxes, multi-line text and other input controls. When the user clicks submit button( or in some case presses enter), the user-supplied values and choices made are sent to the server. If there is some problem with the data supplied by the user (i.e. form submission fails), the values supplied by user and the choices made must be restored. So that he/she don't have to type it again.
The following code is a small form with different type of HTML controls, has the ability to restore the values supplied and options made. Copy and paste this code into a blank PHP file and execute to see how the values are restored.
To create customize shorter teaser, use this snippet
<?php print $teaser = substr($node->content['body']['#value'], 0, 220) ?>
the "220" is number of character before it cut the teaser.