1560, "protected, defended," past participle adjective from guard (v.). Meaning "reserved and cautious in speech, behavior, etc." is from 1728. Related: Guardedly; guardedness.
权威例句
1. He is being guarded by a platoon of police.
有一队警察看守着他。
2. Environmental groups have given a guarded welcome to the Prime Minister's proposal.
环保组织对首相的提议表示谨慎的欢迎.
3. In the office, Dr. Lahey seemed less guarded, more relaxed.
莱希博士在办公室里看起来没有那么谨小慎微,放松了许多。
4. The camp is surrounded by razor-wire fences and guarded by military police.
营地周围架着尖利的铁丝网,且有宪兵看守。
5. Details of its past activities were zealously guarded.