sceptic

The empirical sceptic appropriately responds: how do you know?

经验主义的怀疑可以作适当的反应:你是如何知道的？

The government must still convince the sceptic that its policy will work.

政府仍须使持怀疑态度的人相信其政策可行。

sceptics said the marriage wouldn't last because of the age difference.

持怀疑态度的人认为这场婚姻不会持久，因为双方年龄相差太大。

sceptics tend to harrumph at case histories like this.

怀疑论对这样的个案史常常愤怒地表示不满。