英语i do have one favor to ask请问这个句子为什么要加do?这里的do 如果能举几个这样的句子就更好

No one I do not have one you 英语i don't have an pen.do you one?这个one可以改成its吗?或者改成pen? i have a car.do you have (one/it) I have a cat.Do you have one? 求英语帝翻译：i have crying some day,but i do it no one people no what have i do these days. I want some water,do you have one?改错 I like big purple hats.Do you have one? Only half one year do I just wanna have. Do you think Davied have one?I think ( ). 英语i do have one favor to ask请问这个句子为什么要加do?这里的do 如果能举几个这样的句子就更好 翻译i don't know how to fill it ,[我不知道怎么填写水单】can you do me a favo 请问英语May I have oneMay I have one和Can I have one有区别吗谢谢 英语选择题(要中文,分析)What do you think of the birdge?I have never seen________before.A.so a long one B.so long one C.such a long one D.a such long one I have some pens.Do you need one?Yes,)one to me. How many names do you have怎样答选以下哪个答案A. I have only one. B.I have one. C.I have a name. I have one brother 为什么英语要加one?列如：I don't have one,为什么要加one? How many books do you have?I have one/a book.