(A) Originally developed for detecting air pollutants, a technique called proton-induced x-ray emission, which can quickly analyze the chemical elements in almost any substance without destroying it,
(C) A technique originally developed for detecting air pollutants, called proton-induced x-ray emission, which can quickly analyze the chemical elements in almost any substance without destroying it, A 中, 先状语从句, 后主语+过去分词定语,which 。。 都是围绕主语-technique 。 ETS原则: 过去分词定语尽量紧接修饰对象, 所以 which 没办法, 只能放后面。 C 中, 不符合惯例。 |