根据下列句子的意思及所给的汉语、英语及首字母提示，写出空缺处词语的正确形式。

1. Students should pay attention to l___________ to the teacher in class..

2. Tomorrow is my father's ___________ (四十) birthday.

3. He ran so fast that he ___________ (赶上) the early bus yesterday.

4. She was ___________ (shock) at the news that a volunteer from Hong Kong died in Yushu earthquake.

5. I ___________ (luck) got a chance to be a volunteer for the 2010 World Expo.

羊水内肺表面活性物质迅速增加的时间是（）。

A．25周 

B．28周 

C．30周 

D．35周 

E．40周