What makes tornadoes start?

I wonder...
what makes tornadoes start?
For a tornado to start warm air and cold air mix together which makes a funnel.
The funnel comes down from a thundercloud.
It spins so fast that it can suck up things from the ground  Tornadoes are very dangerous and can do a lot of damage to peoples houses. They can also do a lot of damage to the land and to the animals.
Tornadoes can appear from any direction. Most move southwest, to northeast, or west to east.

A tornado can rip a house into shreds.
When a tornado is coming people are in danger!!! People panic when they hear or know that a Tornado is coming.

People who live where there are tornadoes have ways to keep safe.
During a storm, people can listen to weather reports to see if tornadoes have been seen by other people.

Some scientists study tornadoes. They try find out when they are going to happen. They look for big thunderclouds that could become a tornado. The scientists can warn people if a tornado is coming.

The Tornadoes will often stop in about two or three hours. For a tornado to stop the worm air and cold air separate and the thundercloud will disappear in a few minutes.

BY  TRISTAN!!!