1.观察者；观测者；目击者
You can refer to someone who sees or notices something as anobserver .
e.g. A casualobserver would have taken them to be three men out for an evening stroll...
乍一看的话，还以为他们三人是晚上出来散步的。
e.g. observers say the woman pulled a knife out of the bunch of flowers and stabbed him in the neck.
目击者说那名女子从花束中拔出一把刀来，扎进了他的颈部。
2.观察家;评论员
Anobserver is someone who studies current events and situations, especially in order to comment on them and predict what will happen next.
e.g. observers say the events of the weekend seem to have increased support for the opposition...
观察家说周末发生的事件似乎为反对派赢得了更多支持。
e.g. Political observers believe that a new cabinet may be formed shortly.
政治观察家认为新内阁可能很快就会组建。
3.（监督重大事件或局势的）观察员
Anobserver is a person who is sent to observe an important event or situation, especially in order to make sure it happens as it should, or so that they can tell other people about it.
e.g. The president suggested that a UNobserver should attend the conference.
总统建议联合国应派一名观察员参加本次会议。
1. 观测器：速度估测的方法有的是根据马达的端电压及电流来估测转速,有的是利用输入马达的电压命令及马达的输出电流以估测马达的转速,亦有用观测器(observer)原理得到马达的转速.
2. observer
2. 观察者模式：观 察者模式(observer)完美的将观察者和被观察的对象分离开. 举个例子,用户界面可以作为一个观察者,业务数据是被观察者,用户界面观察业务数据的 变化,发现数据变化后,就显示在界面上. 面向对象设计的一个原则是:系统中的每个类将重点放在某一个功能上,
