The major disadvantage to a closed ca system is the fact that because you are the ca, you need a support structure to handle this responsibility.

封闭ca系统的主要缺点是，因为您就是CA，所以需要一个支持结构来处理这种职责。

youdao

With a closed system, your company is in the business of being a CA.

在一个封闭系统中，您的公司就起着 CA 的作用。

youdao

The Fact is, Apple closed and sold their last assembly facility in Roseville CA in 2002 because it sat unused for more than 3 years.

FORBES: Would You Pay More For A 'Made In The U.S.A.' Mac?