Actual useful years
[经] 实际使用年限
🧩 词语组成解析
n. 年代；岁月；年；年龄
🗣️ 情景例句
Susan, I don't plan to make any decisions Susan
我不打算做决定
It's hard to say.
很难说。
It must have been a gas that could burn but that would not explode, a gas that did not smell strong, and a gas that did not kill people.
它一定是一种能够燃烧而不能爆炸的气体，一种味道不很强的而且不使人致死的气体。