Validity of credit
[经] 信用状的有效期
🧩 词语组成解析
of
[əv]
prep. 关于;属于…的;由…制成;
aux. 助动词 [非标准用语、方言] =have [主用于虚拟语气];
🗣️ 情景例句
Collecting matchsticks was fun, until that fateful day one of them caught alight.
收集火柴是一种乐趣，除非一天其中一根火柴不幸燃烧起来。
It is easy to open a shop but hard to keep it always open.
开设店铺易，维持常开难。
I have 4 books and 2 magazines to check out.
我有4本书和2本杂志要借。