Formal:
* Magandang araw po. Kumusta po kayo? (Good day. How are you?) This is the most polite and formal way to greet someone.
* Magandang hapon po. Kumusta po kayo? (Good afternoon. How are you?)
Informal:
* Kumusta ka? (How are you?) This is a more casual greeting used with friends and family.
* Kamusta ka? (This is a more informal variant of Kumusta ka.)
You can also combine a greeting with a question about someone's well-being:
* Magandang umaga po. Mabuti ba ang pakiramdam mo? (Good morning. How are you feeling?)
* Hello! Kumusta ang araw mo? (Hello! How was your day?)
Note: The "po" is a politeness marker that is used when speaking to someone older or of higher social standing.
It's important to remember that Tagalog has different levels of formality. The best way to learn how to greet someone is to observe how native speakers interact with each other.