Tornadoes are nature's most violent storms, which can cause deaths and destroy a neighborhood in seconds. A tornado appears as a funnel-shaped (漏斗状) cloud from a thunderstorm to the ground with whirling (飞快移动) winds that can reach 300 miles per hour. Damage paths can be over one mile wide and 50 miles long. Every state is at some risk from this disaster.

    Some tornadoes can be seen clearly, while rain or nearby low-hanging clouds obscure others. At many times, tornadoes develop so rapidly that little, if any, advance warning is possible.

    Before a tornado hits, the air may become very still. A cloud of debris (散片) can mark the location of a tornado even if a funnel can not be seen. Tornadoes generally occur near the edge of a thunderstorm, when the strong wind may die down. It is not uncommon to see clear, sunlit skies behind a tornado.

The following are facts about tornadoes:

    The average forward speed of a tornado is 30 MPH, but may also vary from still to 70 MPH. Debris is picked up or a cloud forms in the funnel.

    The average tornado moves from southwest to northeast, but tornadoes have been known to move in any direction. Tornadoes are most often reported east of the Rocky Mountains during spring and summer months.

    Tornadoes can happen together with tropical storms and hurricanes as they move onto land. Waterspouts are tornadoes that form over water.

    The tornado season in the southern states of America is March through May; in the northern states, it is late spring through early summer. Tornadoes are most likely to occur between 3 p.m. and 9 p.m., but can occur at any time.

    A big storm took us by surprise. We didn't 1 to be hit hard so we didn't leave our home. When we realized our yard was 2and more water was coming, it was too late to move.

    We had to climb on3of the roof (屋顶) to get away from the water after it started entering the house. The 4 went off, it was extremely dark and we were 5 We had to tie ourselves to each other, because the 6 was very strong. I had my laptop with me and kept posting cries for7 We stayed on the roof for eight hours 8 we were rescued.

    It was a 9 night. Some people lost their lives. Many houses were completely 10 Our neighbor's roof was blown away.11 although our house was also hit, it remained intact (完整的).

    At present, we keep going back, taking many photos—an requirement 12 the insurance company. We expect them to make an assessment of the damage, and then hopefully,13 our losses. And I'm particularly 14 that my university projects were lost. That means more work for me and I am due to graduate in December.

    We are now 15 at a friend's house in Brooklyn. We won't be able to return to our house in months. There's no information about the support for the 16 of this storm. All we hear is to go to the shelter.

    But now I'm 17 because my family and I are alive. And it's important to18 that there are still people 19 food, shelter, or gas in the cold weather. It's a truly terrible time for the city now but I believe everything will 20.