by day

• Day by day she learnt more about her job
  她日益了解自己的工作了
• They don ’ t work by day but by night
  他们白天不工作，晚上工作。
• The young tree grows taller and thicker day by day
  这棵小树长得一天比一天高，一天比一天粗了。
• State - owned enterprise reform philosophy : approaching perfection day by day
  国企改革哲学日臻成熟
• Owls sleep by day and hunt by night
  猫头鹰白天睡觉，晚上猎食。
• You can see stars by night , but not by day
  你在夜晚可以看到星星
• What is done by night appears by day
  若要人不知，除非已莫为。
• My wife is getting better day by day
  我的妻子一天天好起来了。