IF WE KEEP OUR ENVIRONMENT ______, WE WILL LIVE A HAPPIER AND HEALT...

1. - DE THI & DAP AN HSG 9 NAM DINH
Lớp 9 DE THI & DAP AN HSG 9 NAM DINH

1. If we keep our environment ______, we will live a happier and healthier life.

A. clean

B. to clean

C. cleaning

D. cleanly