Directions：In this section ，you will hear 10 short dialogues．At the end of each dialogue，a question will be asked about what was said．Both the dialogue and the question will be read only once．After each question there will be a pause．during the pause，you must read the four choices marked A，B，C and D，and decide which is the best answer．Then m ark the corresponding letter on the Answer Sheet with a single line through the center．