怎样研究大小单双的规律简介：The calm pool water suddenly started rolling, making gurgling, gurgling sounds, and soon it was boiling, but nothing appeared. After a while, the boiling bubbles gradually subsided, and nothing seemed to happen.
The calm pool water suddenly started rolling, making gurgling, gurgling sounds, and soon it was boiling, but nothing appeared. After a while, the boiling bubbles gradually subsided, and nothing seemed to happen.
