1. But most of the physical differences between originals and copies are so minor that detection of them would require a sophisticated laboratory.
    然而，在母体和克隆体之间存在的身体差异大部分都很小，小得需要在设备精良的实验室里测定。

2. The detection of crime is not always easy.
    查明犯罪不总是一帆风顺的。