下列各组细胞中，一定含有X染色体的是

按要求在下列空格中填出下列有机物的有关式子：

糖尿病患者尿液中含的糖类结构简式　 ____，甲醛（CH₂O）、乙酸（C₂H₄O₂）和果糖（C₆H₁₂O₆）组成的混合物中，氧元素的质量分数是53.3%，则碳元素的质量分数为　 ____

    My name is Jim. I am a student. At school, I have a good friend. His name is Mike. He is tall. He has short hair. We are classmates, too. We go to school at  7:00  o'clock. We go home at  5:00. It's  3:15  now. It's time to play games. Let's go to the playground. We play football with some boys.

They are         too.

爸爸问迈克晚饭想吃什么,迈克告诉他想吃牛肉和面条,迈克该怎么回答：(    )