It depends on the scenarios: If you are making a speech or an address: 各位貴賓 （各位+ honorable guests / Distingushed guests) +大家好 （您們好 sounds from textbook） If you are visiting/receiving a group of professors/Enterpreneurs/Doctors : 各位教授們/企業家們/醫師們 （各位 + title) +大家好 If you are visiting a group of elders/experts with honorable social status : 各位長者們 /賢達 （semi-formal) +大家好

The easiest way is you can say 大家好！

大家好da4jia1hao3 各位上午好ge4wei4shang4wu3hao3 你们好ni3menhao3

You can say: 1. 各位(greeting) 2. 各位(noun)(greeting) Example sentence: 1. 各位早上好 2. 各位老师们大家好