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And how to say"Good afternoon" in Japanese except " こんにちは"

What's wrong with konnichiwa? :)

Good afternoon=こんにちは the native Japanese told me, it is simply wrong. Why they don't answer this question and point out the mistake. I also want to know how are the Japanese to say good afternoon in their own language.

I think something to consider is that saying "Good afternoon" is not always appropriate. I don't mean "wrong" and I don't mean in terms of time. Rather, I think "greetings", in general, are in question here. What I might do when speaking Japanese, instead of saying こんにちは, is ask お元気ですか？ or something similar (and within terms of appropriate politeness).

So, in essence, don't get stuck thinking that you have to greet someone based on what time it is, etc. Think in terms of your relationship with the individual(s) you are speaking with and the context within which you are doing it.

For example, it may be 2:00 in the afternoon, but you haven't seen or spoken with your teacher Mr. Tanaka in about a year, so instead of 田中先生、こんにちは, you would say 田中先生、久しぶりですね！(hisashiburi desu ne! "It's been awhile!").

Hope this helps.

@ Michelle

Discussion
Mr. Kramer and I myself has been trained in the field of law, the training in law is the logic analysis and compliance. For example: between a ten-dollar bill and a hundred-dollar bill, which one will you take?
A. Ten-dollar bill
B. Hundred-dollar bill
C. Both ten-dollar and hundred-dollar bills

The smart people will select C, but the educated people will take B. Since the question is asked which bill. In compliance to the question, B is the best answer.

Here, the question asked, how to say "Good afternoon" in Japanese except " こんにちは". The choice would be:

A. No Change
B. 田中先生、久しぶりですね

In compliance to the question, A is obvious the right answer. How can the answer in B is corresponding to the question.

@Wozitoya

I think it is irrelevant that you have been trained in the field of law. I, too, am an educated person and can make logical deductions and analyses.

However, this is not important. What is important is that I think that you (and thus perhaps others) misunderstood what I was saying.

My point was simply that perhaps considering こんにちは as your only option for greeting someone whom you encounter in the afternoon is limiting. As in English (and other languages), Japanese provides other options depending on your relationship with the person being addressed and the context of the situation.

An alternative I offered was "お元気ですか？” For example, when I would visit my professors during their offices hours when I was in college, they might greet me saying "ヒューズさん、元気ですか？” This implied a closer relationship between us, but was also something akin to "how are you?"

”田中先生、久しぶりですね” was never offered as a direct alternative to こんにちは; rather, it was intended to help the questioner open their mind to the possibilities that might occur in the real world. While こんにちは will still get them through the situation posited with the imaginary 田中先生, it would be less natural. One should choose the words and phrases they use based on a variety of factors, not just one (afternoon or not?); that would be in accordance with a natural and fluent use of language, native or otherwise.