Do dogs understand us? Be careful what you say around your dog.It might understand more than you think. A border collie(牧羊狗) named Rico recognizes the names of about 200 objects, say researchers in Germany. The dog also appears to be able to learn new words as easily as a 3­year­old child.Its word­learning skills are as good as those of a parrot or chimpanzee(黑猩猩)．