短語詞組短語concave spherical surface 凹球面concave ellipsoidal surface 凹橢球面concave rotative surface 凹回轉(zhuǎn)面concave cambered surface 移動擺桿annular concave spherical surface 凹球面環(huán)狀concave aspheric surface 凹非球面concave curve surface 凹曲面Hoop concave spherical surface 仿形加工滾輪凹球面concave -surface 水面下凹 返回 concave surface