Easily add term to vocabulary with long list of terms
For better UI management of taxonomy terms try Taxonomy Manager

This module provides a powerful interface for managing taxonomies. A vocabulary gets displayed in a dynamic tree view, where parent terms can be expanded to list their nested child terms or can be collapsed.

The Taxonomy Manager has following operations and key features:

 - dynamic treeview
 - mass deleting
 - mass adding of new terms
 - moving of terms in hierarchies
 - merging of terms (using the Term merge module in 7.x)
 - fast weight changing with up and down arrows (and AJAX saving)
 - AJAX powered term editing form
 - simple search interface
 - CSV Export of terms
 - i18n support for multilingual vocabularies (per language terms)
 - Double Tree interface for moving terms in hierarchies, adding new
   translations and switching terms between different vocabularies