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In the last 500 million years, there have been five timeslife on Earth has almost ended. Many  (scientist) say we are now entering the Earth's sixth mass extinction. There is  long list of reasons why so many species  (die) out. This time, human activity will be  (blame) because human activity is causing species to die out 1, 000 times  (fast) than normal and has   (negative) affected all other species on Earth, including animals and plants. If a sixth mass extinction  (occur), we would also be  risk of dying out as our world and our lives depend on the balance in nature between animals and plants. In order to stop the sixth extinction, we need to take steps to stop  (destroy) the planet that we live on and start to protect it.