来自于学生自身好动、好奇或好胜心理，如渴望从体育活动中获得身体上的快感、乐趣、刺激，以及希望满足自尊心、上

A. indented.
B. former.
C. original.
D. suggeste

A. He didn"t know the book was a best-seller
B. He"s becoming more interested in the book
C. He"s on his way to the bookstore
D. He has just finished the book

A. mixture.
B. foundation.
C. derivative.
D. simulation.

A. He recently injured his hand
B. He can carry some books for the woman
C. He needs to borrow some of the woman"s books
D. He can"t help the woman until noon