Part B Directions: You will hear four dialogues or monologues. Before listening to each one, you will have 5 seconds to read each of the questions which accompany it. While listening, answer each question by choosing A, B, C or D. After listening, you will have 10 seconds to check your answer to each question. You will hear each piece ONLY ONCE. 听力原文： Hello, I was once an airline hostess. Now I' m on my first bus trip and I' m quite amazed at the services offered during the trip. Included are meals on the way, rest rooms, public-address announcements and a uniformed hostess. Just now I introduced myself to the hostess on the bus, and we compared experience on air and ground travel. At lunch time, she gave out menus offering a choice of sandwiches. As she began filling orders, she found that there weren' t enough egg-salad sandwiches. She quickly went to whisper to the driver. The bus soon stopped. The hostess dashed to another similar bus that was all the time following ours, and soon she returned with a box of egg-salad sandwiches. As she passed my seat, she asked, 'Could you do that on a plane?' Who was the speaker?