Unlike IQ, which seems to be fixed after age five, all of us can work on skills like smiling or a positive attitude, traits commonly found in individuals with high social skills.
智商一般在5岁以后就基本定型了，但微笑、积极的社交态度等有效的社交技能是可以通过努力得到提高的。
2
I had encountered a whole social class of delightful teenage cashiers, smiling at me while they went about their dreary job.
我简直遇到了整整一个社会阶层的开心的年轻女收银员，她们一边对我微笑着，一边忙着手里乏味的工作。
3
In addition, smiling is important for success in the business world and the social occasion.