Animals and machines can use signs
Animals use signs: songbirds mock each other, apes could speak if their vocal chords were different. Differences between human and animal—and machine—use of signs is only a matter of complexity. To make machines like humans, make them more complex.
"Do men and even women make fun of each other better than do the birds who repeat the songs of other birds in such a way as to ridicule them perfectly?"
Julien Offray de La Mettrie (1774, p.152).