按要求完成下面按句子
问题描述：
按要求完成下面按句子
1 Are these his computer games?(改为肯定句）
2 These are backpacks.（改为单数句）
3 His grandfather is my friend.（改为一般疑问句）
4 That is his English dictionary.（改为复数句）
答
1 These are his computer games.
2 This is a backpack.
3 Is his grandfather my friend?
4 Those are his English dictionaries.