引导主语从句同时作从句的主语由谁主持回忆还没有决定。

Who will preside at the meeting has not been decided yet.

youdao

该句子的主干是voices now come from many quarters；句首Just as结构做比较状语，意为"正如...一样"；insisting 引导的分词结构做定语修饰主语voice，分词结构中含有两个并列的由that引导的宾语从句，第二个宾语从句的真实主语是不定式结构to keep... 翻译：就象吸烟问题一样，来自不同领域的声音坚持认为有关全球变暖的科学资料还不完整。

Just as on smoking, voices now come from many quarters insisting that the science about global warming is incomplete, that it's Ok to keep pouring fumes into the air until we know for sure。

youdao

分析：主语：Americans；谓语：say；that引导一个宾语从句，还包含有一个省略了关联代词的定语从句，a person can be sure in life修饰two things. 当先行词在定语从句中作宾语时，常可省略。

Americans often say that there are only two things a person can be sure of in life: death and taxes.(*)

youdao