. Every new thought or idea has to ___ w

英汉互译。

1. buy presents __________________

2. 看大象 __________________

3. go skiing __________________

4. 划船 __________________

5. go ice-skating __________________

冰和水混合物的盆拿到20℃的房间里，在冰熔化过程中

A．冰的温度升高，水的温度不变

B．冰和水的温度都升高

C．冰的温度不变，水的温度升高

D．冰和水的温度都不变

在麻醉兔颈总动脉插管记录血压曲线，再将不同浓度的氯胺酮注入耳缘静脉，观察血压的变化，这种实验方法属于（）。

A.急性在体实验

B.急性离体实验

C.慢性在体实验

D.慢性离体实验

E.临床实践

By the time Bob arrives in Beijing, we have already arrived here for two days.

A．we have been staying here for two days

B．it has been for two days we have stayed here

C．it is already two days before we have arrived here

D．we will have stayed here for two days

以下哪些是万向节或滑动叉早期磨损的原因（）。

A、发动机长时间怠速运转

B、频繁倒车

C、油封失效

D、没有定期加注润滑脂