题目

Mother asked the youngest kid with his toy car. A . what the matter was B . what is the matter C . what the matter is D . what was the matter 答案：D4．根据显微镜结构图回答：（1）用来调节光线强弱的结构是[10]反光镜；（2）转动时，镜筒的升降范围较大的结构是[⑨]粗准焦螺旋；（3）接近观察物的镜头是[④]物镜；（4）取显微镜时，握镜的部位是[12]镜臂．