chin projection

例句：

1. 1. The chin projection is a common feature of many mammals.
   下巴投影是许多哺乳动物的常见特征。
2. 2. During the surgery, the surgeon made a chin projection to guide the cutting.
   在手术过程中，外科医生做了一个下巴投影来引导切割。
3. 3. The chin projection can be used to determine the position of the patient's head in relation to the table.
   下巴投影可以用来确定患者头部相对于桌子的位置。