When the dog entered the stage, he upstaged the actress.是什么意思？

When the dog entered the stage, he upstaged the actress.

这只狗一上台, 顿时抢了女演员的戏.

when

adv. 什么时候，（用于时间的表达方式之后）在那时，其时，当时；conj. 在…时，既然，如果；pron. 什么时候，那时；n. 时间，时候，日期，场合；

例句
It was a Christmas when shoppers passed by expensive silks in favor of more practical gifts.
这是一个购物者不理会昂贵的丝绸衣服而热衷于更实用礼物的圣诞节。

the

art. 指已提到的人（物），指说话人与听者已知的人（物），用于独一无二的事物前，与形容词最高级和序数词连用；

例句
He did have a real knowledge of the country...
他对该国的确知之甚多。

dog

n. 狗，蹩脚货，丑女人，卑鄙小人；v. 困扰，跟踪；

例句
He dropped his sausage on the pavement and someone's dog ate it, mustard and all.
他把香肠丢在人行道上，不知是谁家的狗将香肠甚至连带芥末都吃个了精光。

entered

v. 进入( enter的过去式和过去分词 )，进去，参加，登记；

例句
A waiter entered with a tray...
侍者端着托盘进来了。

stage

n. 阶段，舞台，戏剧，驿站；vt.& vi. 上演，演出，筹办，举行，适于上演，坐公共马车旅

例句
The woman he had seen performing on stage was in actuality quite older than she had seemed.
他所见的那个在舞台上表演的女人实际年龄比看上去要大很多。

he

pron. 他，它，一个人；n. 雄性动物；

例句
Logic had prevailed and he had abandoned the idea.
最终理智占了上风，他打消了那个念头。

upstaged

v. 抢…镜头，使相形见绌( upstage的过去式和过去分词 )；

例句
He had a younger brother who always publicly upstaged him...
他有一个弟弟，总是公然抢他的风头。

actress

n. 女演员，女表演者；

例句
...a famous actress who was accused of being a political agitator.
被指控为政治煽动者的著名女演员