短语词组短语hollow abdomen gravity dam 空腹坝断面hollow arbor gravity dam 空心重力坝stone masonry hollow gravity dam 砌石空腹重力坝hollow arch -gravity dam 空腹重力拱坝stone masonry -hollow gravity dam 砌石空腹重力坝gravity hollow dam 空腹重力坝 返回 hollow gravity dam