請找出下列句子中唯一的錯誤，并改正在后面的橫線上。
1. The children is playing football on the grass. __________________
2. Listen! Who is read English loudly? __________________
3. What are you doing? You're writing a letter. __________________
4. Sandy is siting under the tree. __________________
5. My brothers are haveing lunch at home now. __________________
