如何使用 "exactly" 造句

1. Doctors don 't know exactly what causes autism .
医生对自闭症的发病原因没有确切的看法。
2. Exactly how does the brain accomplish this memory processing ?
如何描述大脑完成记忆处理的准确过程?
3. In fact , governments have done exactly the opposite .
事实上,政府们的所作所为恰恰相反。
4. But that 's exactly the point .
但这就是问题的关键。
5. Exactly who will buy these bonds is unclear since brazilian investors can get a comparable yield without taking on so much risk .
确切地讲谁会买这些债券还不清楚,因为巴西的投资者可以获得类似的收益而同时没有冒那么大的风险。