發送短信 : BEHAVIOUR OF GRAVITY CAISSON ON SANDBED

 _____      ______   _    _      ___      ______  
|  __ \\   /_   _// | \  / ||   / _ \\   /_   _// 
| |  \ ||   -| ||-  |  \/  ||  / //\ \\    | ||   
| |__/ ||   _| ||_  | .  . || |  ___  ||  _| ||   
|_____//   /_____// |_|\/|_|| |_||  |_|| /__//    
 -----`    `-----`  `-`  `-`  `-`   `-`  `--`