cross-sectional area

例句：

1. 1. The engineer calculated the cross-sectional area of the beam to determine its strength.
   工程师计算了梁的横截面面积以确定其强度。
2. 2. The construction company needs to measure the cross-sectional area of the foundation to ensure it is adequate for the structure's weight.
   建筑公司需要测量地基的横截面面积，以确保它足以承受结构的重量。
3. 3. The doctor measured the cross-sectional area of the patient's heart before performing the surgery.
   在执行手术前，医生测量了患者心脏的横截面面积。