Most babies have a closed ductus arteriosus by 72 hours after birth.大多数婴儿在出生后72小时内动脉导管闭合.Babies shed a layer of downy , slender hairs ( lanugo ) before or just after Birth.细毛,在出生前或出生后不久便脱落.Consequently, the problems such...
因为正在使用很多昂贵的设备，所以我非常紧张。I get very nervous because I'm using a lot of expensive equipment.海关官员们对这种设备作出了一系列互相矛盾的陈述。Customs officials have made a series of contradictory statements about the equipment.该设备几个月之前曾投入运行。The ...