I know that nowadays in English the verb "beware" can be used only in imperative clauses and in bare infinitival constructions to warn or to guide. I've understood that nowadays "beware" can't be inflected.
Would it be okay to use "beware" in a subjunctive clause like in "It's essential that she beware of the dog." or does it sound weird or ungrammatical?
Thanks for the help!
Sounds fine to me, but as it turns out, the usage is rather rare. In fact, I could only find a handful of relatively recent examples where it's clearly the subjunctive (by which I assume was meant the use of a plain form of a verb in a declarative content clause allowed by verbs such as suggest, as in I suggest you be on time).
However, I am a suspicious sort and so I suggest to the workers and their trade union representatives that they beware of Tories bearing gifts (2003, Ms Maria Eagle, British House of Commons)
I am aware that Chimamanda Ngozi Adichie well knows this saying by her own illustrious uncle and our icon, Chinua Achebe:' Until the lions have their own historians, the history of the hunt will always glorify the hunter.' In the light of this quote, I would urge that we beware, even in this season of anomie, the dangers of a single story. (Guardian)
Just as she was enjoying the thought of becoming Mrs. B, an anonymous warning arrived , suggesting that she beware of a sham marriage. (Masterplots: Revised Category Edition, British Fiction Series; Frank Northen Magill · 1985)
I would suggest to the Senator that he beware he does not fall into the same error which our former Chairman of the Joint Economic Committee , the former Senator from Illinois - Mr . Douglas - used to fall into (United States. Congress. House. Committee on Ways and Means · 1967)
If I ignored the sign "beware of the bull" on the gate into a field and climbed over the gate, ignoring the warning, and were then tossed by the bull, I wouldn't bother complaining to the farmer. If I did, I would probably get the answer: "Well, I warned you to beware, and you did not beware.".
The Cambridge online Dictionary gives examples of its use, all of which match the idea that 'beware' is never used as an ordinary verb. The examples are of imperative or modal usage.
The fact that beware is not used in all the ways of other standard verbs does not entail that there is a rule against such usage. People don't tend to use it as an ordinary verb for an understandable reason.
Beware is made up of the verb be, and ware. There is a useful account of this in Etymonline: [https://www.etymonline.com/search?q=beware&ref=searchbar_searchhint]
So it was originally (in the 12th century CE) indeed not an ordinary verb to be used in different tenses. "Be" is the base form of the copula, and the base form of verbs is also the imperative form. That did not stop two famous English writers, Dryden and the good Dr. Johnson (the author of the first English dictionary). It is fair to say that some uses seem weirder than others, and that in any case, its main use is on notices rather than in conversation. The word beware for the purposes of everyday language looks moribund. That is a prediction that it will come to look increasingly old-fashioned and so become non-standard. But that does not render it incorrect or forbidden.
As @Tuffy says, beware etymologically originates from the base form be, so it's understandable that it can only take the base form.
The subjective form in a mandative construction can certainly have be as the subjunctive form, so I don't see any reason why the base form beware cannot be used in the construction.
Granted, this usage is few and far between, but at least one 2020 New York Times article (book review) agrees with me:
The 2008 financial crisis is, of course, an excellent example of the ways that the past may be a disastrous guide to either the present or the future. Most of the data leading into the crisis wasn’t much help in predicting it, and the lived experience of most so-called experts didn’t help either. Kay and King skewer pre-crisis pomposity and they tell diverse and fascinating stories about corporate culture, the inequitable remuneration of chief executives, the hunt for Osama bin Laden, the manufacturers of the Airbus, NASA and the traffic app Waze. Their book is demanding, and at times difficult, but it is also an elegant and careful guide to thinking about personal and social economics, especially in a time of uncertainty. The timing is impeccable. The authors advise that you beware experts who use words like confidence, likelihood and probability interchangeably, and never underestimate the value of asking the deceptively simple question: What is going on here?
No. Beware is a defective verb, as follows:
Beyond the modal auxiliaries, beware is a fully-fledged defective verb of English: it is used as an imperative (beware of the dog) and an infinitive (I must beware of the dog). (Wikipedia)
Being able to also be used with modal auxiliaries allows for one to say things like:
While the last example uses the subjunctive mood, it uses it in the "if" clause. The verb "beware" isn't in the subjunctive mood.
Examples of the mandative subjunctive found with Google Books:
But it was not just Bertani who wrote; for all who knew Garibaldi seemed to believe in his need for advice and his accessibility to theirs. A number of them now sent it, redundantly demanding that he "beware of [Giuseppe] La Farina." Raymond Grew; A Sterner Plan for Italian Unity (2015)
His reason still clamored a warning, crying that he beware of this child of the Eldreds, that the only foundation for his hope that her hands were clean and her record free from duplicity was a wild guess. Harold Titus; The Beloved Pawn in Everybody's Magazine, Vol 48 (1923)
Belshazzar listened in surprise to her desperate prayers that he surround himself with every protection, that he beware against venturing out at night, that he wear armor under his tunic, and that he carry weapons of defence always around with him. Margaret Horton Potter; Istar of Babylon (1902)
