C# Expression 创建Lambda表达式树如何嵌套

[写代码的相声演员]

现在有两个类

public class UserGroup{
public string GroupName{get;set;}
public ICollection<User> Users{get;set;}
}

public class User{
public string UserName{get;set;}
public string Password{get;set;}
public string showName{get;set;}
}

现在需要Expression的静态方法创建以下两个树

Expression<Func<User,bool>> exp1 = a => a.UserName == "test" && a.Password == "123456";
Expression<Func<UserGroup,bool>> exp2 = a =>  a.GroupName.StartsWith("Group") && a.Users.Any(b =>  b.UserName == "test" && b.Password == "123456");

问题主要是第二个里的a.Users.Any的Any怎么处理？

[写代码的相声演员]

第一个我自己做出来了

ParameterExpression a = Expression.Parameter(typeof(User), "a");
var exp1 = Expression.Equal(Expression.Property(a, "UserName"),Expression.Constant("test"));
var exp2 = Expression.Equal(Expression.Property(a, "Password "),Expression.Constant("123456"));
var result = Expression.Lambda<Func<User,bool>>(Expression.AndAlso(exp1,exp2), a)

不知道这么写对不对。