練習步驟：
step1：劃分句子結構，找句子主干
step2: 確定修飾詞，修飾短語或修飾從句的修飾關系
step3: 確定代詞指代對象
劍橋雅思9
Reading Passage 1
長難句：For instance, they were used to stain previously invisible microbes and bacteria, allowing researchers to identify such bacilli as tuberculosis, cholera, and anthrax.
step1：劃分句子結構，找句子主干
step2: 確定修飾詞，修飾短語或修飾從句的修飾關系
step3: 確定代詞指代對象
劍橋雅思9
Reading Passage 1
長難句：For instance, they were used to stain previously invisible microbes and bacteria, allowing researchers to identify such bacilli as tuberculosis, cholera, and anthrax.