颠换
参考答案：颠换：碱基替换时，嘌呤为嘧啶代替，嘧啶为嘌呤代替，叫做颠换。
According to the weather report, the temperature tomorrow will rise up ______ 32 degrees centigrade, which I think is quite hot ______ May in Zhejiang.
A．at; in
B．to; for
C．to; in
D．by; for
A．都有燃料进入汽缸
B．将燃料燃烧放出的内能传递给工作物质，使工作物质受热膨胀，对外作功
C．都能把燃料燃烧所释放出的内能全部转化为机械能
D．一个工作循环中有三个冲程都要靠飞轮的惯性来完成
