poor-quality concrete

例句：

1. 1. The construction companyused poor-quality concrete in the foundationof the new building.
   这家建筑公司在新大楼的地基使用了劣质混凝土。
2. 2. The engineerrecommended using high-quality concrete instead ofpoor-quality for the project.
   工程师建议使用高质量的混凝土而不是劣质混凝土进行这个项目。
3. 3.The poor-quality concrete was causing thefoundation to settle and crack.
   劣质混凝土导致地基沉降和开裂。