tiered structure

• 分层结构

tiered structure的用法和样例：

例句

1. When the social structure has undergone a period of annexing, the middle class in our country is coming into shape gradually while developing quickly.
   在社会分层结构进一步分化整合之时，我国的中间阶层也正酝酿成形，并逐步发展壮大。