Take an empty two-liter soda bottle, wash it out, fill it with water, screw the lid on tightly and set it into your toilet tank, as far away from the flapper valve as possible.
拿一个两升的空汽水瓶，洗干净，装满水，旋紧盖子，放进马桶的水箱里，离舌形阀越远越好。
3
If you're hot and thirsty after a 20-minute run in summer heat, it's easy to guzzle that bottle in 20 seconds, in which case the caloric expenditure and the caloric intake are probably a wash.