Kindly answer the questions.
Use of kindly is polite or impolite.
Because it looks like command/order to me.
Can I use this while I writing letter to any person? (e.g. kindly reply me)
It is polite, Gary, but it's not the most polite way to ask something. It can also be used, with the righ intonation, as an order or an expression of feigned politeness/exasperation.
In order to be polite in English, we generally add more words. The examples below go from highest level of politeness to lower levels of politeness.
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I was wondering if you would be willing to [do something].
I was wondering if you would/could (kindly) [do something].
If you wouldn't mind, could you [do something]?
Could you [do something]?
Would you [do something]?
Can you [do something]?
Will you [do something]?
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There are other ways, of course, to ask politely, but this is a good start.
It could also be used sarcastically; a lot depends on the tone of voice and the instruction being given. Riverkid's suggestions would generally be more polite.![]()