Here is the passage again:
My cat Fuzz loves to sleep in inconvenient places. Lately she prefers the
computer table. Where her long hair sticks to the mouse
pad, covers the keyboard, and clings to the screen of the monitor.
The third part is a subordinate clause fragment. This part has a subject, hair, and three verbs—sticks, covers, and clings—but the relative adverb where keeps it from making a complete thought.