1. 下层结构：understressing 应力不足 | understructure 下层结构 | undersuppliedproducts 短线产品
2. 基础：understratum 底层 | understructure 基础 | understudy 预备演员
3. 底座结构：understructure 下层结构 | understructure 底座结构 | understudy 练习做临时替角
4. 底座结构 下层结构：understressing /应力不足/低应力锻炼法/ | understructure /底座结构/下层结构/ | understudy /练习做临时替角/
noun
1. understructure的解释
1. lowest support of a structure
e.g. it was built on a base of solid rock
he stood at the foot of the tower
Synonym: foundation base fundament foot groundwork substructure