每日商务英语 第568期:秘密​的

hush-hush -------- 秘密的（形容词，非正式）

英文释义
(adjective, INFORMAL) Describing something done in secret.

例句
Several engineers in my company are working on some hush-hush project they never discuss with anyone.
我公司的几位工程师正在搞一个极秘密的项目，从不和别人谈论它。