Introducing and Greeting People

Greeting People: 

Hello. / Hi.
Good morning. (before 12 o'clock)
Good afternoon.(after 12 o'clock)
Good evening .

Introducing People:

What's your name?
Who are you?
My name is ...
I am ...
My friends call me ...
You can call me ...
Haven't we met (before)?
Yes, I think we have.
No, I don't think we have.
I think we've already met.
I don't think we've met (before).
This is ...
Meet ...
Have you met ...?
Yes, I have.
No, I haven't.
Yes, I think I have.
No, I don't think I have.
Hello, ... (name)
Nice to meet you. (informal)
Pleased to meet you.
How do you do? (formal)
Nice to see you.
Nice to see you again.
Say Goodbye
Good bye.
Bye. / See you.
See you later.
See you soon.
See you tomorrow.
See you next week.
Good night.

Health:
How are you?
How are you today?
Fine, thank you/thanks.
Not too bad.
Very well.
I'm okay / all right.
Not too well, actually.
What's wrong with you?
What's the matter with you?
Are you all right?
I'm tired .
I'm exhausted .
I've got a cold.