Blue Monday 蓝色的周一。 过完周末回到工作单位或回校上课的周一，心情很郁闷。 After a weekend of playing, people feel sad to have to go back to work/school. So, to be blue means to be sad.

Sleepy Tuesday 爱睏的周二。 年轻学生们形容周二他们在课堂上总爱打瞌睡。（这句形容比较不常用。） 

Hump Day is Wednesday. 周三是（驼）峰天。 到了周三，已经过了一半的工作/上学天了。这有如爬坡一样，现在已经越过了坡顶，正朝着周末走下坡路了。Wednesday is the middle of the work or school week. So，once you get to Wednesday you are half way to the weekend.  It's like you have been climbing a hill and now you have gone over the top and are on the downhill side heading for the weekend.

TGIF - Thank God It's Friday. 谢谢上苍，终于是周五了。 周五过后就是周末了，人们总是开心的说这句话。 It's the last day of the work and school week. People are so happy that it's Friday and almost the weekend.  They say, TGIF.  Thank God It's Friday.