短語(yǔ)詞組短語(yǔ)count -down 準(zhǔn)備時(shí)間讀數(shù);計(jì)數(shù)下降;遞減速計(jì)數(shù)英語(yǔ)Count -Down counter CD 遞減計(jì)數(shù)器 返回 count-down