完型填空 另外答案上说One day,the doorbell rings and she opened_____the

完型填空 另外答案上说One day,the doorbell rings and she opened_____the door.opened为什么不用单三
Mrs Green loves flowers very much and she has a small but beautiful garden.In summer the flowers are very n_______.One day,the doorbell rings and she o______the door.She sees a l________boy outside.He is about seven years old and has a lot of f_____in his hands.I'm selling flowers,he says,do you w______any?They're very cheap.I pick t_____this morning.M______boy,Mrs Green answers.I have a lot of flowers in my garden.S______I needn't pay for them.Oh,no,you don't have any flowers in your g________now,says the boy,they are all here in my h_______.

Mrs Green loves flowers very much and she has a small but beautiful garden.In summer the flowers are very nice.One day,the doorbell rings and she opens the door.She sees a little boy outside.He is about seven years old and has a lot of flowers in his hands.I'm selling flowers,he says,do you want any?They're very cheap.I pick them this morning.Morning boy,Mrs Green answers.I have a lot of flowers in my garden.So I needn't pay for them.Oh,no,you don't have any flowers in your garden now,says the boy,they are all here in my hands.
书上的答案有时候也是有错误的,整篇文章都是一般现在时,故用opens.