text: Lee: Any of you going to the gym tonight?
  Sam: What time? 
  Lee: About 9 pm?
  Tom: I can't
  Sam: Why? 
  Tom: I'm working
  Lee: Can't finish that in the morning?
  Tom: No... 
  Sam: Ok, so I'll be there before 9
  Lee: Ok, CU
target: Lee and Sam are going to the gym about 9 pm, but Tom can't as he's working.