decrease/dIˋkris; dIˈkriːs/v [I,T] to become less, or to make something do this [ increase ](使)减少﹔(使)降低: Crime decreased by 30%. 罪案减少了 30%。+to By 1881, the population had decreased to 5.2 million. 到 1881 年﹐人口已减少到 520 万。the need to decrease costs 降低成本的需要 —decrease /ˋdikris; ˈdiːkriːs/n [C,U] a decrease in sales 销售量的减少