题目

Only after some minutes ______ speaking. A. did the warden start                                    B. the warden started        C. had the warden started                                      D. the warden had started 答案：A9．要得到一次函数y=3（x-2）的图象，必须将一次函数y=3x的图象（　　）A．向左平移2个单位B．向右平移2个单位C．向左平移6个单位D．向右平移6个单位