bummed and bummed out. They both mean to be unhappy or upset. 意思是不高兴，感到烦恼

example: I\'m really bummed that I have to get up so early! I\'m also bummed out that Dr. Wu is teaching this class. I\'ve heard she\'s really tough.

Chill or chill out：  means to relax 这里是指休息

example: Glad class is over! I\'m ready to chill for the rest of the after. I haven\'t had a chance to chill out these last few days, getting ready for school and all.

 Have fun chilling tonight at my friends\' house.

下一篇：

天天英语：Greasy spoon / Potluck. Pot