The centre of the city is spotlessly [stainlessly] clean.

市中心一尘不染干干净净。

《新英汉大辞典》

The University of Tennessee's Walters Life Sciences building, is a model animal facility, spotlessly clean, careful in obtaining prior approval for experiments from an animal care committee.

田纳西大学的沃尔特斯生命科学大楼，一尘不染，是一座典型的动物实验楼，在获得动物委员会对实验的事先批准方面十分谨慎。

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The house had huge, spotlessly clean rooms.

那房子里有着宽敞而且一尘不染的房间。

《柯林斯英汉双解大词典》

Typescripts that used to be cut, pasted and blue-penciled are spotlessly digital now.

WSJ: As Trash Goes, Authors' Clutter In the Right Hands Is Very Bankable

Cooking is therapy for Estrada and the kitchen - a spotlessly clean room with all the modern trimmings - is his inner sanctum.

CNN: DAYS OF THEIR LIVES

On our visit on Tuesday, the beach was spotlessly clean.

BBC: NEWS | UK | Wales | North East Wales | Beach faces tide and untidyness