VOA慢速英语:Smoking -- The Leading Cause of Preventable Death

find sth to be，find后面是宾语补足语的形式。

2. Studies have found that nicotine can be as difficult to resist as alcohol or the drug cocaine.

as as

as…as 结构的基本用法
　　其基本意思为“与……一样”，其中的第一个as副词，其后通常接形容词或副词(用原级)，第二个as可用作介词(后接名词或代词)或连词(后接从句)。使用时应注意以下几点：
　　1)在否定句中，第一个 as 也可换成 so：
　　He doesn’t study as [so] hard as his brother. 他学习不如他弟弟努力。
　　2) 在该结构的两个as之间通常接形容词或副词的原级，但若涉及数量或程度，可用“as much+不可数名词+as”和“as many+可数名词复数+as”：
　　You’ve made as many mistakes as I have.  你犯的错误和我犯的一样多。
　　I haven’t got as much money as I thought. 我不像原来想像的有那么多钱。(R2/92)
　　其间接形容词时，有时该形容词还可修饰另一名词，但这个名词应带有不定冠词(注意词序)：
　　She is as good a cook as her mother. 她和她妈妈一样是位好厨师。
　　也可说：She is a cook as good as her mother.
　　但不说：She is as a good cook as her mother. 或They are as good cooks as us.

3.The American Cancer Society says blood pressure returns to normal twenty minutes after the last cigarette.

return to normal恢复正常

例句：Seventh, our work in education, science and culture has begun to return to normal.
      第七，我们的教育、科学、文化工作，开始走上了正轨。