Stepped aging
[化] 阶段时效
🧩 词语组成解析
v. 踏；行走（step的过去式和过去分词）
aging
['eidʒiŋ]
n. 老化;老龄化;（酒等的）陈化;熟化;
v. 使变老;（使）长大( age的现在分词 );使显老;使变老;使苍老;
🗣️ 情景例句
Are you ready to make a ten-percent down payment? Payments over 30 years?
你能支付 10% 的首期房款吗？三十年按揭吗？
How much is it by registered mail?
挂号信要多少钱？
You must always return your library book on time!
你必须按时归还图书馆的书！