Echolucent
[医]无回音区
🗣️ 情景例句
The selection here is very large, it may be difficult to choose.
这里有很多式样可以选，可能很难决定。
How long has it been since you've heard from your uncle?
自从你听到叔叔的消息有多长时间了？
I'm sorry,I'm don't know.
很抱歉，我不知道。