naysayer

1. One naysayer pointed out that these athletes were simply reverting to the mean.
   一位反对者指出，这些运动员只不过是从巅峰状态回复到了平均水平。
2. A dysfunctional team, or even one naysayer in a critical position can stall your investment.
   团队运转不良、关键岗位上的员工爱唱反调，这些都可能会阻碍创业者获得投资。
3. Be warned that the majority of people out there will go into naysayer mode automatically.
   值得注意的是，这类人大多数都会自动的变为反对者。
4. Under pressure from vulnerable and poor states in Africa and elsewhere, it has shifted from naysayer to supporter of a global deal.
   在来自非洲和其它地区脆弱且贫穷国家的压力之下，中国已从一项全球协议的反对者变成了支持者。
5. When you have such an event in prospect, the naysayer who argues that you are over-reacting is more likely to be right than wrong.
   如果预计此类事件，则认为你反应过度的那些反对派更有可能是正确而不是错误的。
6. If a naysayer close to you has been difficult and critical, there's a good chance that you've finally silenced that person.
   如果你身边有个和你唱反调的人，很难相处又老爱批判你，那么这个月有个很好的机会让这个人彻底闭嘴。
7. Every naysayer is negating people and things around them consciously and unconsciously, while also being negated by other naysayers.
   每一个否定者都在自觉或不自觉地否定周围的人或事，但是否定者通常也会遭遇其它否定者的再否定。
8. We can say the hidden writer is the highest level naysayer, the way he negates is also of the most concealing.
   可以说隐含作者是小说的最高否定者，他的否定方式也是最隐蔽的。

noun

1. someone with an aggressively negative attitude