我有兩個(gè)看起來(lái)像這樣的實(shí)體：public class Account{    public int AccountId { get; set; }    public string AccountName { get; set; }    public decimal AccountBalance { get; set; }    public virtual Expense Expense { get; set;} }public class Expense{    public int ExpenseId { get; set; }    public string ExpenseName { get; set; }    public decimal ExpenseAmount { get; set; }    public virtual ICollection Accounts { get; }}如果我想要一個(gè)新添加Expense到DbContext.Expenses與Account已經(jīng)存儲(chǔ)中的對(duì)象Database，做我還需要這個(gè)新添加Expense到Account Entity？在我的測(cè)試中Expenses，Account Model如果我只是創(chuàng)建一個(gè)新Expense實(shí)體，則無(wú)法從訪問(wèn)關(guān)聯(lián)。