WHAT CAUSE A VOLCANO ERUPTION (process analysis)

Volcano eruption is natural event so we may not guess when it will happen.When volcano eruption happens it affects people's life negatively and it damages many thinhg immediately.Well there is a question."What cause a volcano eruption?"
Firstly, when a volcano eruption happens the most dangerous thing is lava blow because lava damages everythimg on its way.After lava blow it is hard to stop it.Maybe we can change its way but whatever we do, we cant stop it.Lava damages people, animals, trees, buildings, gardens, parks...etc.Lava can cause of deaths because it happend immediately and lava moves fast so we may not have time to escape.In fact before the volcano eruption,volcano gives signals but after eruption everything can be late.Lava isn't only danger, there are many danger.
Secondly another effect is tufa.In fact we can say it, tufa effect.Tufa is kind of dust cloud but tufa is more dangerous than dust.Tufa can reach other places thanks to winds.After volcano eruption, tufa clouds diffuse large areas, so tufa doesn't affect only volcano are.Tufa causes air pollution so all flights and maritme matters can call off.This is volcano's undirect effect on people.
Thirdly volcano eruption damages environment.this situation affects people and animals.People and animals lose their homes because environment is home of people and animals.Volcano eruption effect can continue long time and it is hard to fix after it because when volcano eruption happens, environment pollution occurs.We can say this situation has link with lava and tufa.Environment pollution is not last effect of volcano eruption.Volcano eruption changes people's life but this changing is in a bad way.
At last volcano eruption affects all things negatively on its way.There are a hopeless point.It is fact that we cant predict volcano eruption before it happens.Volcano eruption always occurs so we must be ready.