杯水的上部应该是凹面的。
The water surface in the cup is slightly vaulted upward.
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当采用凹面轴肩时，材料流动状况更明显。
The results indicate that the concave shoulder can make the material flow better.
镜子呈凹面。
The mirror is concave.
应用推荐
模块上移
模块下移
不移动