链传动由()、()和从动链轮三个基本构件组成.
参考答案:主动链轮;链条
—______ do you think of your new lifestyle?
—_______. [ ]
A. How, It's OK.
B. What, It's OK.
C. How, Very much.
D. What, Very well
中学教师教学研究的课题一般应来自学术前沿中的问题。