What season of the year ends when the ancient festival of Samhain started?
Autumn (and the end of the harvest season).
Look at the picture. What vegetable is this historical lantern made of? 
A turnip
Did people wear costumes in ancient times for fashion or for historical tradition?
For historical tradition.
Where did the original Halloween tradition start: in Europe or in South America?
In Europe (Ireland and Great Britain).
What season comes right after autumn?
Winter.
Before people used pumpkins, what vegetable did they carve in Ireland and Scotland?
Turnips (and potatoes/beets).
What did ancient people build outdoors to stay warm during cold autumn nights?
Big bonfires 
How old is the history of Halloween: about 200 years old or more than 2,000 years old?
More than 2,000 years old.
Why was the end of October important for ancient farmers?
Because it was the end of the harvest and the preparation for cold winter days.
Why did people switch from carved turnips to carved pumpkins in America?
Because pumpkins are native to America, bigger, and easier to carve.
In the past, what materials were used to make masks and costumes?
Animal skins, straw, and old fabrics.
Was Halloween originally a commercial party or a seasonal community celebration?
A seasonal community celebration.