请问what are the major threats to coral reefs?

请问what are the major threats to coral reefs? Beacuse of the pollution,the c_____ coral reefs are dead and The scientist began to study the coral reefs eight years ago Coral reefs under the ocean are___every colour,every size an They are not the kind of people to _______ to threats. The threats to the health of astronauts in space are very di what are the major technology for mixing process?How to judg what are the major types of CLAUSE in english?try to illustr 英语翻译Table 20.2 lists the major threats in the HRM/payroll cy what are the major differences between the cultures of Brita What are the two major parts of the Bible? what are the major legal systems in the world today