observer
单词辨析：
指因爱好或工作而观察某人、某事物的人。
More than ten thousand bird watchers visit annually.
每年有万余名观鸟者到访。
Where is the fire watcher?
火灾警戒员在哪里？
At that moment, the watchers became strangely quiet.
在那个时刻，那些观察家变得出奇地安静。
指戏剧、电影等的观众或演讲、音乐（会）等的听众，为集合名词；作主语时，若强调整体则其谓语动词用单数形式，若强调多个成员则其谓语动词用复数形式。
The audience was enormous.
观众人很多。
The audience were greatly moved by his words.
听了他的话，观众们很感动。
The performance caused a roar of laughter in the audience.
表演引起了观众的哄堂大笑。
His lecture drew a large audience.
他的讲座吸引了一大批听众。
指对某些事件、局势、事物等进行长期或定期观察的人，这些人被视为相关方面的专家。
conomic/political observers
经济观察家/政治观察员
The observer should take full notes on the atmospheric conditions.
观测者应对大气状况作详细记录。
An acute observer usually sees the essence of things at first sight.
敏锐的观察家通常一眼即可看出事物的本质。
指只在一旁静观事件发生或事态发展而不介入其中的人。
Onlookers gathered around the scene of the accident.
旁观者围聚在事故现场。
Her manner is that of an onlooker.
她采取的是一种旁观者的态度。
Some onlookers joined the marching demonstrators.
一些旁观的人加入了游行示威的队伍。
尤指体育赛事的观众，也指某些公共活动（如演出、游行等）的观看者。
About 10,000 spectators were watching the game.
约有1万名观众在观看比赛。
Thousands of spectators came to the city for the horse race.
数以千计的观众来到这座城市观看赛马。
The policeman asked the spectators to stand back.
警察要观看者退后。
相关例句：
A close observer would have noticed it.
若是一位细心的观察者，早就会注意到这个问题了。
The observer should always make full notes about the atmospheric conditions.
观测者要对大气条件作详细记录。
Does she deceive India? India is an observer state to the Shanghai Co-operation Organisation.
她是不是也骗了印度？印度是上海合作组织的观察员国。
The old man was sent along as an observer.
那个老人被派做观察员。
The talks took place in the presence of a diplomatic observer.
会谈是在一位外交观察员在场的情况下进行的。
A poll for the Observer showed Labour on 39 per cent with the Tories lagging a point behind
《观察家报》一项民意调查显示，工党支持率为39%，保守党落后其1个百分点。