How do you do!

[Pheakdey]

Dear Sir/ Madam,
I am writing to ask for how to use "how do you do" because it is very hard to say in my country Asia, Cambodia. Especially, for the most of the children who are just four or five years old they can not remember what time that they should say the words as goodmorning, goodafternoon, or goodevening. So they can say "how do you do" dayfully, can't they?
This is the big deal that stuck in my mind about two weeks ago. I firmly hope all of you will help me to deal with this issue. And I am looking forward to receiving your generosity.
Best Regard
Pheakdey

[Joe]

Sorry, but "How do you do?" is only used formally, and only the first time you meet someone.

To keep it simple:
good morning: midnight to noon
good afternoon: noon to 1800
good evening: 1800 to midnight

Or to keep it simpler still, they can say "hello" (or "hello, how are you?") all day and all night

See also: http://www.englishclub.com/vocabulary/t ... -night.htm

[Pheakdey]

I'm pleased to say thanks that you were able to help me how to solve this problem for me EC. I will take your good advice to practise. And if you don't mind, can you show me how to download audio or MP3 or link profile? Because it's very hard for me to find any material to support my English Teaching due to I was being a part from the downtown.
I would be grateful to see your help.
Best Regards
Pheakdey