原文如下：
这里有处错误：当我们对AutoReset Event对象调用SetEvent()，该Event不会丢失。下文引自MSDN：
When the state of an auto-reset event object is signaled, it remains signaled until a single waiting thread is released; the system then automatically resets the state to nonsignaled. If no threads are waiting, the event object's state remains signaled.
