twogridadj.双栅极的twonum.二；两个two-dimension code二维码Two -shot grouting双液注浆two-gas space suit双气体航天服two key cryptosystem双密钥密码系统two - stage drying二级干燥two-layer equation双层式two points threshold两点阈two-stage producer[化] 两段发生炉two to one principle[经] 二对一原理two-screw oil pump双螺桨油泵