1  Staff "went through the confirmation process that they were not adult products several times," said the statement. 

这里的that引导的是同位语从句。

2.It is a mark of how China has changed that its first-ever Civil Code, a fat volume of laws covering everything from marriage to property rights, approved on May 28th, revises adoption rules to make it easier for children to be raised in private homes.

It为形式主语，划线部分为真正主语从句。its first-ever Civil Code为从句的主语，revives为从句的谓语动词。approved on May 28th为过去分词短语，作主语的非限制性定语。

3.Those changes reflect a broader easing of laws that, from 1980 to 2016, restricted most urban families to a single child. 

easing为名词化的动名词（verbal noun)。名词化的动名词用如名词，即可以被限定词限定，被形容词修饰，不可以直接后接宾语，宾语由介词of引出。