the thing isEXPLAIN spoken used when you are going to explain something, give the reason for something, or give an opinion 问题是；原因是 ‘It sounds like a good idea. Why don’t you invest?’ ‘Well, the thing is, I can’t afford to.’ “听起来是个好主意。那你为什么不投资呢？”“唉，问题是我没钱投资。”
the thing is that The thing is that you can’t always judge your own work. 问题是你不能总是自己来评价自己的工作。
the thing is that• And the thing is that it was just crazy!
→ the thing is at thing(4)