Originally Posted by HarleyBob
.....but they would even look better if you made the tongue out of leather instead of cardboard.
I think, you misunderstand the photograph.
The tongue is the small bit (in the same leather as the uppers) that you see coming out of the shoe. The larger ‘cardboard’ bit is an adjustment to the last. A piece of leather has been attached to the last, to give the finished shoes a bit more room over the instep.