题目

根据下面各句句意及汉语提示词，写出该单词的正确形式（每空一词）。【1】The singer had never _____________ (表演) in New York before.【2】If I have made any mistake, I’m ready to _____________ (道歉).【3】It may rain, but _____________ (无论如何) I shall go out. I don’t mind the rain.【4】The flashing light was a _____________ (信号) that a train was coming.【5】It is my _____________ (信念) that God helps those who help themselves.【6】She is the type of person who _____________ (成功) anywhere.【7】The dog enjoyed himself _________在平面直角坐标系中，三角形ABC的三个顶点的坐标分别为A（-5，0），B（4，0），C（2，5），求S△ABC．