As for whether yellow dogs with black tongues are good taxi dogs, there is actually no absolute answer to this question, because it involves a lot of subjective evaluations and personal preferences.

First of all, a yellow dog with a black tongue does not itself represent the breed or quality of the dog. A dog's appearance characteristics, such as coat color, tongue color, etc., are only part of their genetic inheritance and have no direct connection with the dog's personality, health, IQ, etc.

Secondly, there is no clear definition of the word Shigu. It may refer to native dogs, local dogs or dog breeds in a specific area. Taxi dogs in different regions may have different appearance characteristics and personality traits, and these characteristics also vary from person to person.