单项选择题
I. Text Understanding. (20%)
Directions: In this section, there are some questions based on Text One and Text Two in this unit. Please choose the right answer from the four choices marked A, B, C and D after you finish all the learning materials.
Text One
1. In this passage, we all listen to music on _____ separate planes.
A、2
B、3
C、4
D、5