Here psychologist, Dr Alex Mielke, explains why to BBC World Service programme, CrowdScience.

心理学家亚历克斯·米尔克博士向BBC全球服务节目《大众科学》中解释了原因。

Dr Mielke uses the term, significant other, to describe any kind of romantic partner who you have a long-term relationship with.

米尔克博士用“另一半”这个词来描述与你保持长期关系的任何浪漫伴侣。

Dr Mielke also notes the difference between two words people often confuse: jealousy, and a similar term, envy - wanting what someone else has.

米尔克博士博士还指出人们经常混淆的两个词之间的区别：嫉妒和一个类似的词，羡慕——想要别人拥有的东西。