Add/Edit Email field not shown when editing a contact
It may be possible that email field is disabled from your Display Preferences. You can find this on Administer -&gt; Customize Data and Screens -&gt; Display Preferences. 

Make sure Email field is checked TRUE on Contact Details Column of Editing Contact Section.

Demo Link - http://dmaster.demo.civicrm.org/civicrm/admin/setting/preferences/display?reset=1