Formal:
* 早上好 (zǎo shang hǎo) - This is the most common and polite way to say good morning, suitable for most situations.
* 您早 (nín zǎo) - This is a more respectful greeting, used when addressing someone older or of higher status.
Informal:
* 早 (zǎo) - This is a more casual way to say good morning, suitable for friends and family.
You can also use 早上 (zǎo shang) by itself, which literally translates to "morning" and is often used in casual situations.
It's important to remember that the tone of voice and body language can also affect the meaning of a greeting. A smile and a friendly tone will make your greeting more welcoming, regardless of which phrase you choose.