One, while we choose to implement a two-tier approach for production purposes, we did test Portal Enable on single-tier system and it worked flawlessly.

第一件，虽然出于生产目的，我们选择实现两层方法，但我们在单层系统上测试了Portal Enable，它运行良好。

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The effective abolition of the separate state second pension, and its incorporation into the new enhanced single-tier version, will end the complicated system of so-called "contracting out".

BBC: 'Simpler' flat-rate state pension unveiled

The Queen's speech is likely to propose an end to the multiple-tier appeal system for asylum seekers, replacing it with a single level of adjudication.

BBC: Call for radical asylum changes

The union also wanted the introduction of a single pay arrangement for cabin crew staff, rather than the existing two tier system, with staff who joined after 1997 being paid less than those employed before that date.

BBC: The deal came after 120 hours of negotiations