According to surveys by the National Institute on Drug Abuse, about 20 percent of young adults used cocaine in 1979, twice the number reported in the 1977 survey.
=According to surveys by the National Institute on Drug Abuse/, about 20 percent of young adults used cocaine in 1979/, twice the number reported in the 1977 survey.
#根据调查国家吸毒研究学会的/大约百分之二十的年轻人吸食可卡因在1979年/，这个数字翻番在1977年的调查中。
*这个句子很容易理解，像the National Institute on Drug Abuse的专有名词可以不管它，认识与否都不影响我们对句意的理解。
The lawyer for the defense charged that she suspected the police of having illegally taped her confidential conversations with her client and then of using the information they had obtained to find evidence that would support their murder charges.
=The lawyer for the defense charged/ that she suspected the police/ of having illegally taped her confidential conversations with her client/ and then of using the information/ they had obtained/ to find evidence/ that would support their murder charges.
#辩护律师指控/她怀疑警察/非法录下了她和她客户的秘密谈话/并且用这些信息/他们获得的/去找到证据/支持他们的谋杀指控。
*这句话讲的是和法律有关的事，murder的出现，令人毛骨悚然。但仔细琢磨意思并不难理解，注意charge这个多义词的理解，本句中 charge 出现了两次，词性也不一样。
