他们很多也生产铜矿，铜矿常常是和黄金矿井并肩而立。
Many produce copper, too, since it often sits in the same ore bodies as gold.
但金矿公司不会，他们很多也生产铜，这是由于金矿与铜矿通常位于同一矿石层。
Gold miners are not. Many produce copper, too, since it often sits in the same ore bodies as gold.
手机应用程序已经成为了开发者的金矿，让开发者通过销售扔小鸟的游戏(指愤怒的小鸟)获利而不是开发生产力项目挣钱。
Mobile apps have become a gold mine for developers, letting them make money from everything from productivity programs to bird-flinging games.
应用推荐