No matter how the math works out, you persistently view restaurants with voluntary tipping systems as being a better value, which makes it extremely difficult for restaurants and bars to do away with the tipping system.
2016年12月四级真题(第一套)阅读 Section C
On one recent day, this doctor was Daniel Nadeau, wandering the cereal aisle with Allison Scott, giving her some ideas on how to feed kids who persistently avoid anything that is healthy.
2018年12月四级真题(第一套)阅读 Section B
柯林斯高阶英汉双解学习词典释义
ADV-GRADED
一次又一次地;一直
If something happens persistently, it happens again and again or for a long time.