A sample for "温柔而又坚定地说NO",

1.This is a good suggestion.I will ask xxx(your boss) if I should do it next.

Then no what matter what your boss say,This is your boss's decision,not order from your co-worker.Got it?

这可是立场问题，是屁股做在哪里的问题，不能含糊。如果你做了同事让做的事，而你老板不同意，老板问你：who is your boss?
你怎么回答？

The way you thought for NO is rude.

Why? this is your job. you want me to do your job?
Nope,I am not gonna do that