With so many people _________ by sending E-mails every day, it will become more and more important to have a good knowledge of the internet．

1. A.
   communicating
2. B.
   communicated
3. C.
   communicate
4. D.
   to communicate

With so many people _______________ by sending E- mails every day, it will become more and more important to have a good knowledge of the Internet.

   A. communicating         B. communicated       C. communicate        D. to communicate