题目

下列有关声现象的说法中不正确的是（ ） A . 男低音独唱时由女高音轻声伴唱，则男低音比女高音音调高，响度大 B . 男低音独唱时由女高音轻声伴唱，则男低音比女高音音调低，响度大 C . 射击运动员在训练和比赛中戴耳塞，是为了减弱进入耳朵的噪声 D . 宇航员在月球上进行谈话时，听不到对方的声音，这说明声音在真空中不能传播读短文，根据短文内容填词 　　I am Sam. I am American. I have a sister. My father and mother work in China. My sister and I are in the same school. I am in Class TWO,Grade One and my sister is in Grade Two. There are forty students in our class. Twenty-four of them are boys. They are all Young Pioneers. I like playing games with them. We are friends. Miss Liu is my teacher. She is a good teacher. I like the school. 　　Sam is ________. He is now in China with his father and mother. They have two ________. Sam and his ________ are in the same ________.There are ________ boys and girls in Sam's class. They are ________ Young Pioneers. They and Sam are ________. Miss Liu is a teacher and ________ is good. Sam likes the school.