A. Trom 3. Unless we A. predict -. Today the beach is very dirty and full of garbage; A. so B. because C. therefore . People have worked hard to improve their living standard, A. do they B. haven't they C. don't they D. have they A D. conservationist A. plumber who works to protect the environment from damage or destruction. C. consumer B. electrician Jean cloth is very strong and hardly A. tears at B. puts on our water resources, there will be a shortage of clean water someday. C. replace D. conserve B. use we all must clean it up D. if C. takes off D. wears out a show to raise money for the poor children.