1) Adam can be so dense-headed sometimes; it feels like talking to a brick wall.

2) I tried to explain the concept to Mary, but she remained dense-headed about it.

3) He's so dense-headed that he doesn't understand even the simplest jokes.

4) Despite my best efforts, my dense-headed brother still couldn't figure out how to use the new software.

5) The dense-headed student struggled to grasp the algebraic equations.

6) My dense-headed coworker continuously makes the same mistakes despite being corrected multiple times.

7) I find it frustrating how dense-headed some people can be when it comes to understanding basic principles.

8) Sheila's dense-headed nature makes it challenging to communicate with her effectively.

9) It's exhausting to argue with someone who is so dense-headed and refuses to consider different viewpoints.

10) I realized my friend was dense-headed when she failed to see the consequences of her actions.