One of the panels had become detached from the main structure.

一块镶板已从主体结构上脱落。

《牛津词典》

A path, marked by a long concrete wall leads the visitor away from the main structure toward a workshop complex consisting of a two-story square building.

一条靠近长长的混凝土墙体的小径将参观者带离主体建筑，通向一座两层的工厂建筑。

youdao

It describes the main structure and special feature of this new design.

对其主要结构及特点进行了较为详细的论述。

youdao

This creates the main structure of the coral reef.

VOA: special.2010.08.10

He says creating a plan for the structure of the book listing the main ideas makes writing much easier.

VOA: special.2009.10.12

In March 2010, fire almost completely destroyed the Muzibu Azaala Mpanga building, the main structure at the site which contained four royal Buganda tombs.

UNESCO: Brasilia Field Office News Archive

The main structure of Christ's cross was in front of me.

CNN: Amid the wreckage, worker finds affirmation of faith

The main structure was a three-story building with few windows facing the outside of the compound, and a third-floor terrace had a seven-foot privacy wall, they said.

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