单项选择题
Questions 18 to 20 are based on the following passage. At the end of the passage, you will be given 15 seconds to answer the questions.Now, listen to the passage.
How old was Leonardo da Vinci when he moved to Milan（）
A．25. B．30. C．35. D．40.
单项选择题 I must leave now（） if you want that book I'll bring it next time.
单项选择题 Which course(s) runs or run for one hour each time（）
单项选择题 According to the talk, the owner of a bike has to （）
