How quickly or easily would human beings and aliens establish regular communication? It would be easier if both sides wanted to communicate and recognized the problems. In first contact with Ythri, the first problem is for human beings to recognize that the winged Ythrians are intelligent. In Poul Anderson's Technic History and ForLove And Glory, there is recognition that inter-species communication must be to some extent superficial. There would be dialogue about matters of common interest but we can scarcely expect to penetrate the inner thoughts or feelings of an alien being. The British sf writer, Bob Shaw, criticized Larry Niven for having Puppeteers converse like Harvard professors. Shaw had aliens but never any conversations with them.
A first attempt at communication is to repeat sounds heard or gestures seen. In Larry Niven's and Jerry Pournelle's The Mote In God's Eye, a Motie Mediator, i.e., a specialist in communication, amuses the human spaceship crew by instantly and accurately mimicking one man's theatrical shrug of incomprehension. More on this subject later.