题目

—Have you finished doing all the exercises the teacher gave you yesterday? —Yes,completely._____is left. A.None                   B.Nothing         C.No one                      D.Neither 答案：A不吃早餐的学生，往往在上第二节课时，出现头昏、心慌、四肢无力等现象。出现上述现象的原因是A.血糖低于160 mg/dLB.体内缺少必需的氨基酸C.血脂浓度过高D.脑组织得不到足够的能量供应