a two-tiered system的用法和样例：
- The South American Rugby Championship is a two tiered annual tournament for South American teams.
- You want to go with a company that has at least a two tier program because this will allow you to earn residual income.
- A ticket tout offered me a two pound ticket for ten pounds.
- The court granted the company a two weeks stay of execution.
- The typewriter is sold with a two years guarantee.
- You need a two game advantage to take the set.