Scure
[经] 保证; 安全的
🗣️ 情景例句
She has the ability to speak English fluently.
她能够流利地说英语。
Have you heard from Marry?
你收到玛丽的来信吗？
Once the existence of this wave-length had been discovered,
一旦这种波长的实际存在被发现，