题目

       on his past mistakes, Ted realized that he had stayed around the wrong peop1e.A．To reflectB．Reflected C．ReflectingD．Being reflected 答案：C解析:考查非谓语动词。此处reflecting作伴随状语， reflect跟主语Ted之间是主动关系，故选C，意为，反思他以前犯的错，Ted 意识到了他跟一群不应该在一起的人呆在一起。抛物线y=-x2-2x的顶点坐标为    ．