人们都知道如果身上痒,通常抓几下就能解决问题。但这究竟是何原理?美国科学家通过科学实验,揭开了“抓痒”的奥秘。原来抓痒能让向大脑传递刺激的神经细胞变得“迟钝”,从而减轻痒感。这一事实表明①思维和存在具有同一性②实践是认识的目的和归宿③实践是认识的基础④人脑是意识产生的物质基础
There's no __________in the way they do their accounts(记账).
There are too many difficulties for us __________. Wereally don't know __________ to do.
You'll find taxis waiting at the bus station __________ you can hire to reach your host family.
Thetest measures mathematical __________.
This piece of news was __________ economic and social problems.