The other half received a placebo, an inactive substance.

VOA: special.2009.09.30

Sometimes subtle changes in the structure of a protein can convert it from an active state into an inactive state.

有时蛋白质结构上一些很小的变化,就能将其由激活态转变为非激活态

耶鲁公开课 - 生物医学工程探索课程节选

It's a gene that allows you to deliver a drug that's not active but the gene causes that active - that inactive drug to be converted into an active form that kills the cell.

这一方法利用该基因激活,另一种已经导入细胞的非活性药物,来杀死肿瘤细胞

耶鲁公开课 - 生物医学工程探索课程节选

But the group has been largely inactive since 2005, when Mr.Abbas was elected on a platform of reaching a negotiated peace with Israel.

VOA: standard.2009.12.26