画一条数轴，用数轴上的点把如下的有理数：﹣2，$\frac{3}{2}$，0，﹣4$\frac{1}{2}$，1，﹣0.5，4，﹣1 表示出来，并用“＞”把它们连接起来．

向日葵种子粒大（B）对粒小（b）是显性，含油少（S）对含油多（s）是显性，某人用粒大油少和粒大油多的向日葵进行杂交，结果如图所示．这些杂交后代的基因型和表现型的种类分别是（　　）

    If you want to travel to a new place, what will you worry about first? The answer may be how to1the way.

    In big cities many people go from one place to2by bus, taxi or underground. The bus is a popular3of travelling.  If you want to use a bus  you should (应该） know4bus to take. You should5the timetable (时间表) right so that you can take the6bus and get to your place on time. And it's important for you to know7to get off.

    In the countryside (农村), 8can be much simpler (简单). In some places with small roads, people get to school or their offices by9. In my hometown we usually take a boat to school. In other places, students can go to school10foot because they live near the school.