1. Buy crabs and soak them in salt water for about 30 minutes.

2. Crab (páng xiè) is a crustacean, belonging to mollusca and DECAPODA. Its body is protected by a hard shell and breathes through its gills. Taxonomically, it is the same kind of animal as shrimp, lobster and hermit crab. Most kinds of crabs live in the ocean or offshore areas, and some live in fresh water or land. Common crabs are Portunus trituberculatus, Portunus trituberculatus, Eriocheir sinensis and Eriocheir sinensis (Eriocheir sinensis, Eriocheir sinensis and Eriocheir sinensis). A small number of crabs grow and breed completely in fresh water, and most of them live under rocks in mountain streams. There are also a few crabs, such as ground crabs, which can adapt to land life, make holes in wet mud holes and migrate to the sea when breeding.