history: My co-worker agreed to help me finish the tasks even though he was not obliged to. I could not meet the deadline without him The deadline for the work project was coming in two days and I was not done yet. Thankfully_comma_ my co-worker agreed to help me even though he was not obliged to
current: That was nice of him. You should take him out for dinner.
next: I think I owe him. I wish every co-worker was like this in every workplace. What a wonderful world this would be