急：Efile765 form ,but missed several Questions

and also citizanship should be Canada,but picked USA by mistake.The missed Questions are Date of last entry,place of last entry, Manner of last entry and current immigration status.真不知道怎麽填的。後悔死了。可Form certified already.請問，我怎麽可以糾正錯誤？是否可以重新填表，然後和supporting DOC一起寄過去？謝謝各位。