Introduction to Web Accessibility

Here's another attempt at rewording the introductory sentences in the 
Introduction to Web accessibility document.
Current wording:
Web accessibility means that people with disabilities can use the Web. 
It means that people can perceive, understand, navigate, and interact 
with the Web effectively.

Suggested rewording: 
Web accessibility means that people with disabilities can use the Web by perceiving, understanding, navigating, interacting, and contributing to the 
Web effectively and efficiently.
Libby