开放式的楼梯通向较低的楼层。
Most of Africa is urbanizing at a lower level of income than other regions of the world did.和世界其他地区相比，非洲大多数地区的城市化进程是在一个较低的收入水平上进行的。
The bottom line here is the more fiber you eat, perhaps, a lower level of hormone in your body.此处的要点是，你吃的纤维越多，你体内的激素水平就越低。
