Indetectable
a. 不可察觉的,不易发现的
🗣️ 情景例句
Chairman Mao said it is necessary to drill as much as possible.
毛主席说，反复操练是非常必要的。
The moon is a moon whether it shines or not.
或名或暗，月亮总是月亮。
Why? English is the first language in none of these countries.
为什么？在这些国家中英语都不是第一语言。