[] (about a system) having two levels （制度）两级的，双层的，双重的◆a two-tier system of interest rates 利率双轨制◆a two-tier workforce (= where people are paid different rates for doing the same job) 同工不同酬◆They operate a two-tier structure with management and supervisory boards. 他们采用管理委员会和监督委员会这样的两级架构。