What are you up to?
这句常用句的意思是：最近在忙什么?
A: I haven't seen you around lately. What are you up to?
A: 最近没见到你。 在忙什么呢?
B: I'm working two jobs right now. It's killing me.
B: 我现在做两份工作。很累很累!
"It's killing me." 是表示某事很折腾人的意思。
再如"Her singing is killing me." 她的歌声很难听!。