Re: What do we say after work? Don't use "more power to you" in the States in this sort of situation. It has an implication of "you shouldn't/ it's pointless for you to do this thing you're doing, but if you really want to . . . "
"Way to go" is used after a task/job has been completed, but keep in mind that it's sort of juvenille - you wouldn't hear a boss saying that to an employee, for example (unless it was being used sarcastically).
"Good job" is used after a task/job; it's pretty generic and can be used in most situations.
"Keep up the good work" is used either during or after a task/job and can be used in most situations. This one is the closest I can think of to #2 in your first post. "Don't work too hard" is the closest translation, but I don't think it's common to say "Thanks" after it . . . unless it was your boss telling you, "Don't work too hard . . . take the rest of the day off!" :)
(A more common response to "Don't work too hard", as far as I know, is "Yeah, I'm about to finish up," or "Well, I have to get this done". Stuff like that.) |