《鲁滨逊漂流记》的作者是根据()来写这本书的
参考答案:一些航海家和流亡者的记载
已知函数y=-x3+bx2-(2b+3)x+2-b在R上不是单调减函数,则b的取值范围是________.
Doctor Nathan is said to have been ________ to researching into wild animals in Africa for more than
ten years.[ ]
A. absorbed
B. devoted
C. concentrated
D. engaged