Mack knew this passage by heart.麦克会背这一段。You must keep repeating the lines until they are known by heart.你必须反复朗读这几行一直到能背诵为止.The boy learned the poem by heart.这男孩背下了这首诗....
The vibration behaviour of sandwich structure with spring interlayer is studied.研究了具有弹性夹层的层板结构的振动特性.Sandstone type uranium deposits in interlayer oxidation zone are large or super large and in - situ leachable.层间氧化带砂岩型铀矿...