The red door clashed with the soft, natural tones of the stone walls.

这红色的门与柔和自然色调的石墙不协调。

《柯林斯英汉双解大词典》

Draw a house with a red door.

画一幢有一扇红色大门的房子。

youdao

Click on the school's red door to go to class.

在学校的红门上按一下，进入教室。

youdao

Obviously, it doesn't mean "come in" in the sense of the red light over a street door.

当然，它不像临街灯一样表示,进来吧。

耶鲁公开课 - 文学理论导论课程节选

All right. Just some other examples: a red light over a street door.

好吧，现在让我们看看例子：,临街门上的红灯。

耶鲁公开课 - 文学理论导论课程节选

The legendary Romanian facialist moved 10 years ago to the management side as global chief creative officer for Red Door Spas, but is now offering her services through a two-hour uber-facial at the Chatwal Hotel's Red Door Spa in Manhattan.

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Built in 1800, Hank McNeil's Neo-Georgian 13, 000-square-foot Rittenhouse Square mansion is red brick and cube-shaped, with rectangular double-hung windows all aligned and a red front door flanked by Corinthian columns.

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