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With a colleague or acquaintance, both are too formal, really. Something like Sit here a minute, OK? would do.
Being overly formal, however, is better than being underly so, and is certainly not necessarily seen as sarcasm or disrespect-- these are shown more in tone of voice and behaviour.
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You’re right. Of course, ‘Sit here a minute, OK?’ would be better…
Unfortunately, in some situations and with some people (even colleagues) there is a need to be a bit formal…
But not ‘too much’.
That’s right.
But it reminded me the classic “only-after-you” situation - with two men before a door, when they both try to surpass each other in politeness.
Also I’ve heard the English expression I will if you will