“开辟荆榛逐荷夷，十年始克复先基。”这句诗反映的重大历史事件是（    ）

根据不少证据推测，煤是由古代的____堆积慢慢形成的。

完成句子。
1. It's not just because they ____（不能理解它是什么意思）.
2. F 2 F ____ （表示面对面）.
3. Homophone often use letters and numbers that ____（听起来像单词或单词的一部分）.
4. I don't think twelve-year-olds should be allowed to ____ （穿耳洞）.
5. I think teenagers should be allowed to____（与朋友们外出）.
6. If we can't wear our own clothes, we should be allowed to____ （设计自己的校服）.
7. I get nervous before big parties and then I ____（出皮疹）.
8. It isn't good to borrow your friends' books ____ （未经允许）.
 9. My life ____（有了很大的改变）in the last few years.

下面是有关燕麦实验的示意图，图中所示燕麦胚芽鞘的某些部位纵向插入了云母片。请分析图中a至f的琼脂块中，生长素含量正确的一组是(　 　)