我會set 時間, 冲好晾就比1或 2 分鐘時間佢玩, 小朋友掂會知1分鐘有幾長, then, I will explain to him, 1min equal to 60 seconds, 2 mins equal to 120 seconds and so on, depend on how long you allowed. I will count from 1 to 60 loudly, when I count to 60, then, I will turn off the tap. No one is allowed to turn it on again. 佢想開都唔比,