单项选择题A.When she read the text.B.When she asked a question.C.When she explained the text.D.When she turned to write something on the blackboard.
单项选择题A.Casual contact with AIDS victims will not lead to AIDS.B.Publics don’t know how AIDS spreads yet.C.There are many ways of contact in catching AIDS.D.Doctors don’ t know how to prevent the spread of AIDS to others.