当你专心作答试题时,参与的高级中枢主要有()
①下丘脑
②大脑皮层H区
③大脑皮层S区
④大脑皮层V区
⑤大脑皮层W区
A.④⑤
B.③④
C.②③
D.①③
参考答案:A
– Where does your brother work, Jane?
-- In America. But he __________in China for 5 years.
A.has been working
B.has worked
C.worked
D.was working
前者是物理变化,后者是化学变化的一组是[ ]
A.水结成冰 夏日阳光下车胎爆炸
B.酒精挥发 酒精燃烧
C.铁生锈 电灯通电发光
D.光合作用 人的呼吸