位于大脑外侧沟深处的是（）。
A、额叶
B、岛叶
C、颞叶
D、枕叶
E、顶叶
参考答案：B
Every possible means ________ to prevent the air pollution, but the sky is still not clear. [ ]
A. has been used
B. are used
C. is used
D. have been used
为什么电力网要进行升压改造？
