It has to be part of a theory, and then trying to adjust it so it can be incorporated, you discover anti-particles.

要想使理论合理,然后试着去调整,使之和实际相符,结果就找到了反粒子

耶鲁公开课 - 基础物理课程节选

You have to be able to get the DNA into the cell, it has to be incorporated into a vector of some sort, and the vector has to be compatible with the species and the cells that you've provided the DNA to.

你必须把整合在,某种特定载体上的DNA导入细胞,载体也必须和,受体物种,及细胞匹配

耶鲁公开课 - 生物医学工程探索课程节选