题目

.（2010·浙江诸暨中学高三第一次月考） 9. It was too noisy outside. Not until I shouted at the top of my voice ______ his head. A. did he turn B. had he turned     C. he had turned     D. he turned 答案：A已知抛物线，过其焦点且斜率为1的直线交抛物线于、两点，若线段的中点的纵坐标为2，则该抛物线的准线方程为 ．