Ayubowan (āyubōwan) ෴ ආයුබෝවන්
"Ayubowan" is the word used in Sri Lanka to greet someone. It means Long Life. One is Generally greeted by joining two hands in prayer-like manner and saying "Ayubowan". This phrase can be used any time of the day. However, in the city it is more common to be greeted with a hand shake, while the village folks still greet you in the traditional way.
You don't need to use ayubowan all the time to greet someone. You can use simple hello or hi. More people of Sri Lanka can speak or understand English. But you need to speak slow with some people. So they can easily understand you.