线程问题

我做了一个随机显示消息的WinForms应用程序,用两个标签(lblMessage和lblMessageEnglish)实现持续移动的效果
         private void Form1_Load(object sender, EventArgs e)
        {
            Thread obj = new Thread(new ThreadStart(Display));
            obj.Start();
            Thread objEnglish = new Thread(new ThreadStart(DisplayEnglish));
            objEnglish.Start();
        }
        private void Display()
        {
            for(int i=1;i<=100000;i++)
            {
                Random objRandom = new Random();
                int x = 0;
                int y = 0;
                x = objRandom.Next(400);
                y = objRandom.Next(400);
                lblMessage.Left = x;
                lblMessage.Top = y;
                Thread.Sleep(500);
            }
            
        }
        private void DisplayEnglish()
        {
            for (int i = 1; i <= 100000; i++)
            {
                Random objRandom = new Random();
                int x = 0;
                int y = 0;
                x = objRandom.Next(400);
                y = objRandom.Next(400);
                lblMessageEnglish.Left = x;
                lblMessageEnglish.Top = y;
                Thread.Sleep(300);
            }
        }
第一次可以正常执行，但以后就不行了！
我先结束这个进程，然后运行会出现“线程间操作无效: 从不是创建控件“Form1”的线程访问它”指向DisplayEnglish函数中的
lblMessageEnglish.Left = x;语句!
请教一下怎样处理！