Beware of deer crossing this road.
If you need to be cautious of hitting a deer when driving on a dark road, this is an example of when you need to beware of deer.
Origin of bewareassociated, association with be, imperative + ware, but probably from Old English bewarian, to keep watch from be- + warian, to watch, be wary
verbbe·wared, be·war·ing, be·wares
Origin of bewareMiddle English ben war ben to be ; see be . war on one's guard ; see ware 2.
(third-person singular simple present -, present participle -, simple past and past participle -)
- (defective, intransitive) To use caution, pay attention (to) (if intransitive, construed with of).
The verb beware has become a defective verb and now lacks forms such as the third-person singular simple present bewares and the simple past bewared. It can only be used imperatively (Beware of the dog!) or as an infinitive (You must beware of the dog or They told me to beware of the dog).
The inflected forms bewares, bewared, and bewaring are called obsolete in Fowler's Dictionary of Modern English Usage, along with the simple indicative "I beware". The forms bewares and bewared are very rarely found in modern texts, though bewaring is slightly less rare. These inflections are more likely to be found in very old texts.
The meanings conveyed by the obsolete inflected forms may be easily achieved by splitting "be" and "ware", conjugating "be", and possibly replacing "ware" with the more modern "wary"; thus, "bewares" > "is wary", "bewared" > "was wary", etc.
be- + ware