Chocolates that melt into a gooey mess at the bottom of a bag on a sweltering day are one inconvenience that people living in the warmer parts of the world know all too well.

• 大家都知道在闷热的天气下，袋子底部的巧克力常会融化成黏糊糊的一团，对居住在较炎热地区的民众尤其不便。