The towns people are gathered together for the annual lottery that happens. The lottery is a traditional thing they do. It says in the story that "Every year, after the lottery, ..." Line 62. As you can tell from the story the lottery is a annual thing.
Tone and Theme
"The flowers were blossoming profusely and the grass was richly green" Line 2-3. The story was describing what the town looked like at the moment. It also was describing what season they are in. The story also was setting the setting.
In lines 117-119 it says "She tapped Mrs.Delacroix on the arm as a farewell and began to make her way through the crowd". Mrs.Hutchinson taps Mrs.Delacroix on the arm saying bye. She did this as like a farewell because she spotted her family. This is a simile.
The tone was filled with fear. Nobody wanted to get the dot on their little piece of paper. The lottery scared everyone and this dot means you were chosen. Nobody wanted to be chosen.