Professor Bob Chen got his Bachelor degree in China in 1987, and then he went to the United States for his Master's and Doctoral degrees. He was a tenured professor in an American University and had many graduate students from the United States, China, Mexico, and South America. However, since 2017, he has been appointed as an adjunct professor at a university in Shanghai and has taught in Shanghai every year since.In sum, Professor Chen has experienced communications with different kinds of people since 1987.Question 1: When Professor Chen studied in American Universities, his communication with Amercian professors was _____________.Question 2: Now Professor Chen has been teaching in America for over 30 years, his communication with his American colleagues is __________.Question 3: Professor Chen's communication with his students in Shanghai is ____________.