Why there are so many gate in same colors and style pair by pair?

为甚麽那麽多一双一对同颜色与花款的铁闸？

youdao

More venerable abodes are fronted by thick red doors outside of which perch either a pair of lions or a pair of drum stones.

很多庄严的住宅前都有着厚重的红色大门，每扇门上都有狮子门环，门前有石鼓。

youdao

The poster tiger should be created from Zhou's photos by polished the head part by adding a pair of large and clear ears, a pair of canines and some clear beard and hairs around the face.

墙画虎应该是创建自周照虎，修饰了头部，增加了一对大而清晰耳朵和一对犬牙，在脸周围增加了一些清晰的胡须和虎毛。

youdao

The same village was hit by a pair of suicide-bombers on August 13.

VOA: standard.2009.08.29

When you say that, it implies that the differential is given by this pair of partial derivatives.

这就意味着，内能的微分,等于偏u偏T，保持体积不变。

麻省理工公开课 - 热力学与动力学课程节选

If somehow you could take your anti-sense molecules that you've made and you could get them into cells, then by this process of hybridization they would naturally form a pair like this.

如果你能得到合成的反义链,并能使它进入细胞,那么通过杂交,它们就能自然形成这样的一对

耶鲁公开课 - 生物医学工程探索课程节选

Not having James on the floor showed immediately as Georgia turned it over on its next two possession, helped by a pair of blocked shots by Jemerigbe, the second with 51 seconds left.

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But the decision was criticized by the pair's lawyer, and by their coach Christos Tzekos, who was also suspended.

CNN: Katerina Thanou

This vulnerability was nearly exploited by a pair of Nazi saboteurs in November 1944, but their plot was scuppered by an FBI manhunt.

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