The calligrapher uses two ink trays at the same time to hold a bowl of ink and a bowl of water. According to the relevant information, after writing for a while, the water in the ink evaporates and the brush absorbs more ink, making it drier. The resulting problems are that the brush does not focus, cannot be pulled, and the written lines are too white. If there is more, the water content of the ink needs to be increased and it needs to be dipped in water.