如何使用Linq在某些操作中聚合两个列表？

using System;
using System.Collections.Generic;
using System.Linq;

public class Program
{
    public static void Main()
    {
        List<int> list1 = new List<int>() { 1, 2, 3 };
        List<int> list2 = new List<int>() { 4, 5, 6 };

        List<int> mergedList = list1.Concat(list2).ToList();

        foreach (int num in mergedList)
        {
            Console.WriteLine(num);
        }
    }
}