Quality index number
[经] 质量指数
🧩 词语组成解析
index
['ɪndɛks]
n. 索引;<数>指数;指示;标志;
vt. 给…编索引;把…编入索引;[经济学]按生活指数调整（工资、价格等）;
vi. [机械学]转位;
in(in)+dex(proclaim)→指针；索引；指数；食指；指标
🗣️ 情景例句
I can't believe I'm hearing this!
我不能相信我在听这些！
That's too late.
那太迟了。
and by measuring the time interval between the taps and the receipt of the echoes, the depth of the sea at that point can be calculated.
测出回声间隔的时间，便可算出该处海洋的深度。