为什么不是Why do you know that,而是How do you know that

为什么不是Why do you know that,而是How do you know that ____ do you know that do you know that/if Do you parents know that? Idiots,know that you do not know :How do I let you know that you are my Do you know why that bridge is there? you do know that 和 you know that区别 Do you know that后为什么是动词过去式,前面不是有do吗? How do you know that I suffer from insomnia是什么意思? --- Do you know how much that dictionary costs? —How do you know that she likes singing?