15.Known as tuanzhang in Chinese, their duties included liaising with suppliers, informing residents of delivery updates, and organizing volunteers to deliver the goods.
18.In your job maybe you " liaise" with... this means like formally... formal way to speak to people from different organisations or outside your job itself.
19." You don't seem to need many qualifications to liaise with Muggles; all they want is an OWL in Muggle Studies: Much more important is your enthusiasm, patience and a good sense of fun! "
20.He's already liaised with the managers of the theatres we're going to visit, and he's also arranged for an officer of the National Theatre in Munich to show us around the theatre one afternoon during our stay.