assumed datum

例句：

1. 1. The assumption that the earth is flat has been proven wrong by many scientists.
   许多科学家已经证明地球是平的这一假设是错误的。
2. 2. The company's assumption about the market demand was based on incomplete data.
   公司对市场需求的假设基于不完整的数据。
3. 3. The decision to build a new office was based on assumed costs and benefits.
   决定建造新办公室是基于假设的成本和效益。