A common assumption in metaphysics and the philosophy of language is that the general structure of language displays the general metaphysical structure of the things we talk about. But expressions can easily be imperfect representations of what they are about. After clarifying this general point, I make a case study of a recent attempt to semantically analyze the nature of knowledge-how. This attempt fails because there appears to be no plausible bridge from the linguistic structure of knowledge-how reports to knowledge-how itself. I then gesture at some other places where the connection between linguistics and metaphysics is commonly, but illegitimately, assumed.