"Píšeš tou novou tužkou?"

Translation: Are you writing with the new pencil?

[dan379710]

Tužka can also mean ballpoint pen. If you want only pencil, you should use obyčejná tužka

[VladaFu]

Nope. A ballpoint pen is propisovací tužka (colloquially propiska) or kuličkové pero. Certainly not just tužka. If someone is being non-specific, they can perhaps say tužka in general, to mean any kind of writing instrument, but as a translation it is incorrect.

[Pohybel1]

can't it be
are you writing with this new pencil?

[VladaFu]

This course, at least currently, makes a consistent distinction

this - touto, touhle, touhletou
that - tou, tamtou, tamhletou