这里为什么用could呢?You can buy as much as spaghetti as you could.在You can buy as much as spaghetti as you could.中,could 可以换成can吗?这里为什么用could呢?前面不是can吗?

could you come with me,please?这里为什么用could 而不用can 呢? 这里为什么用could呢?You can buy as much as spaghetti as you could.在You can buy as much as spaghetti as you could.中,could 可以换成can吗?这里为什么用could呢?前面不是can吗? Could you tell me where the copier is,please?这Could you tell me where the copier is,please?这里的could能换成can嘛,为什么要用could呢? Nobody could ever replace you为什么用could不用can 改错-Could you help you?-Yes,I could.答案把yes,I could改成yes,I can,为什么呢? 过去式I wish I could fly.这里为什么要用could?不用can? I could eat a horse. 我饿极了. 为什么这里不用can呢? Could you please tell me how can I get to the post office?我记得Could you please tell me 后面应该跟的是陈述语序.为什么这里不是呢? could 是can的过去式,那为什么could you help me 用could,又不是过去式 The bottle is empty． Could I have a full one?第二句的 one我知道是代表瓶子.could是can的过去式,为什么这里要用can的过去式呢?用can不行吗?为什么.. there's an awful lot you could tell about a person by their shose这里的could（为什么不用can而用could）有时候不时的出现过去式,不懂为什么 what would you do if you ( )live your life over again?为什么用could/a.can b.could为什么could could you tell me your name这里为什么要用could? what you said和what you have said有什么区别例如,i can not understand what you ( ).这里要用哪个?如果前面的can改成could呢? he asked if anyone could help him.这里为什么用anyone呢为什么不用someone呢 he asked if anyone could help him.这里为什么用anyone呢为什么不用someone呢? I'm so glad you could come.为什么用could而不能用can? I guess I could come over.为什么用could不用can呢