What are the similarities between ancient Greek theater and modern theater?

Similarities between ancient and modern theater:

1) there was a stage where the actors performed;

2) the main role was played by one or several actors around whom the whole action took place;

3) They staged tragedies, comedies, etc.

There were a lot of differences. For example, only men could play in Greek theater, emotions were portrayed using masks. Also, the Greek theater was open-air and was held only during the daytime.