1. The sandstorm is a horrible phenomenon. The
clouds of dust are so heavy that you can hardly breathe. It
is so dark that it may cause traffic accidents.
2. Droughts result from lack of water, which is essential
for plants and animals. The failure of crops leads to food
shortage, and sometimes even famine.
3. The flood washes away houses, destroys fields, and causes
life and property losses. People may be left homeless and
suffer diseases.
4. The increase of disasters is mainly caused by human activities.
With the growth of population, we need more resources from
the Earth. The deforestation, over-cultivation, together with
other factors, lead to the imbalance of the ecosystem. And
this in turn causes more natural disasters.
Lead-in
