VOA Special English - Development Reports

Lesson 44: Secret of DEET Could Lead to New Insect Products

Scientists finally discover how the world's most widely used repellent works.

 
Audio files and text copyright belongs to www.voanews.com . Codes copyright belongs to www.epangsoft.com.
This program is distributed under the permissons of epangsoft.com. More information, please contact epangsoft.com