为什么是Do you know how old he is而不是he is?

how do you know How do you know? 为什么是Do you know how old he is而不是he is? How do I know you? how do you do的回答为什么是how do you do Do you know how large China's population is?这句话中,为什么是China‘s 而不是 Chinese? 1/为什么是Do you know how many colours there are in the rainbow?而不是Do you know how many colours are there in the rainbow?2/How many colours are there in the rainbow?是否正确? how do you do 后边为什么是问号? 为什么是Do you know what is the matter How high is Qmolangma?Do you know?(合并为一句) Do you know ___ ___ ___? How does he go to school ?Do you know?合并为一句 Do you know ____ _____ to school? do you know how much i love how much do you know really about do you know how to write How many color do you know? HOW MANY COLORS DO YOU KNOW? HOW MUCH DO YOU KNOW ABOUT How much do you know about AIDS