How do we know that we have problems

How do we know that we have problems Sure.I know how to do that. we don't know how to do that.We don't know what makes us laughhow 后边为什么加 to 而what后不加呢 为什么不是Why do you know that,而是How do you know that How do we know the ocean is friendly?英语智力题 how do we know the ocean is friendly?英语谜语 猜谜 how do we know the ocean is friendly? How do we know the ocean is friendly? how do we know the ocean is friendiy? Just know now that we separate have how my daring,do u know how much that i miss :How do I let you know that you are my If I do not know how good that the翻译 How do you know that I suffer from insomnia是什么意思? a cheap slut!That do not know shame,but even do not know how to die I do not know that we have no how do you know How do you know?