Question

how can you say that earth is still very active

Answer 1

The push in volcanic activities, the frequent earthquakes, and other ecological activities share us the information that the world is still growing.

Answer 2

we can  say that earth is still very active by

1)there is still life existing on earth
2)earth is still rotating , revolving around the sun
3)there is existence of gravitational force 
4)there are many active volcanoes 
5)there is occerance of earthquakes because of movements of tectonic plates