I'm posting some basic phrases (as listed on ChamorroLanguage blog) just to start us off:

Welcome - Bienbenidu
Hello - Hafa Adai
How are you? - Hafa tatamanu hao? / Hafa mamaoleka?
I'm fine - Maolek ha yu / Todo maolek
Long time no see - Apmam tiempo ti uli'e hao
(It's a long time since I've seen you)

Apmam tiempo ti uli'e hit
(It's a long time since we've seen each other)

What's your name? - Hayi na'an-mu?
My name is ... - Na'an-hu si...

Where are you from? - Taotao manu hao?
I'm from ... - Taotao ... yu

Pleased to meet you - Ma'gof yu sa umali'i hit
Good morning - Buenos dihas
Good afternoon - Buenos tatdes
Good evening - Buenas noches
Goodbye - Adios
Good luck - Suette!
Cheers/Good health! - Hago lao!
Have a nice day - Puedi ha todo maolek
Bon appetit - Buen prubechu
Bon voyage - Buen biahe
I don't understand - Ti hu kumprende
Please speak more slowly - Pot fabot na despasio i kuentos-mu
Please write it down - Tuge' papa pot fabot
Do you speak Chamorro? - Kao siña hao fumino' Chamorro?
Yes, a little - A'a, didide' ha

How do you say ... in Chamorro?
Hafa taimanu un sangan ... gi fino' Chamorro?

Excuse me/Sorry - Dispensa yu
How much is this? - Kuanto baliña?
Thank you - Si Yu'us ma'ase (lit: God have mercy)
Response (You're welcome) - Buen prubechu

Where's the toilet? - Manu na gaige i kemmon?

Leave me alone!
Sappe! Litira hao! Basta ma estotba yu!

Help! Fire! Stop!
Ayuda! Guafe! Basta!

Call the police!
Agang i polisia!