I see such sentences all the time and I'd like to learn more about their grammatical structure (e.g. how they are described in grammatical terms), their meaning and how to use them in different contexts.

Please let me know whether I can be of help.

The part that I am interested in learning about is be of.

There is a similar question here but the questioner was asking only whether it was correct or not, but I would like to learn the meaning more broadly as I described in my opening sentence.

  • That sounds like a word for word translation of a foreign expression, such as the Italian "essere d'aiuto", rather than something a native would say (e.g., "if I can help you")
    – badp
    Nov 5, 2011 at 17:00
  • 3
    You might find iit simpler if you parse of help as the syntactic unit - which could be replaced by helpful, useful, etc. - rather than seizing on the fact that of help can in principle be completely omitted (which is grammatically quite a significant change, in that help thereby becomes a verb rather than a noun). Nov 5, 2011 at 17:06
  • 2
    My impression is that "be of" can only go with a limited number of nouns. Googling, I find "be of use", "be of service", "be of aid", "be of help", "be of benefit", "be of interest", "be of age", "be of influence", "be of value", "be of account", "be of danger", "be of relevance". But to choose an arbitrary noun, I don't think "be of security" would be used by native English speakers. Nov 5, 2011 at 17:07
  • 1
    I agree with Fumble and Peter. To be of help is just an idiomatic phrase, in modern English. Nov 5, 2011 at 17:59

2 Answers 2


As far as I can tell, there are only a limited number of nouns that work with "be of". I would classify them as idioms. I am listing the most common ones I can think of, where commonness is judged by Google Ngrams. I have grouped them into sets of near synonyms. There are

be of use,
be of help,
be of aid,
be of service,
be of assistance;

these idioms mean that something/someone can be used, can help, can aid, can serve, or can assist. There are also

be of relevance,
be of importance,

which mean that something is relevant to/important for the current subject of discussion. Also,

be of value,
be of benefit;

these mean that something is valuable, usually with respect to the current subject of discussion. Also

be of interest,

which means that something is interesting.

And for a slightly different "be of" idiom, there is

be of age,

which means that someone has reached adulthood.

If you are learning English, it should be fairly easy to figure out what one of these constructions means. But I would suggest that if you use this construction, you should treat it like an idiom, and memorize the specific phrase(s) you want to use. Many nouns describing attributes, like "security" or "tact", cannot be used with "be of". (Google books gives a few instances for "be of security"; it seems to have been used occasionally in the 19th century, but it sounds very strange today.)

  • 5
    +1 Also, off the top of my head, someone/something can similarly be of high/low quality, be of a piece, be of a kind, be of one mind, be of good cheer, be of the opinion (that...)
    – user13141
    Nov 5, 2011 at 18:35
  • Wow! That was a very comprehensive answer. Nov 5, 2011 at 20:12
  • Also, "be of concern". There are probably a bunch more I missed. Nov 5, 2011 at 23:12
  • Also, one can "be of sound mind". Nov 6, 2011 at 0:33
  • @EllieKesselman It was a long answer, but not comprehensive, and almost just plain wrong. Even though the construct isn't used in all cases These phrases are NOT idioms, and there is no comprehensive list
    – Stephen C
    Feb 19, 2019 at 21:46

This is covered under section XIV of the OED’s entry for of:

Indicating a quality or other distinguishing mark by which a person or thing is characterized, identified or described. Used for the Old English genitive, French de; equivalent to the genitive of quality or description.

  • I'm not sure that completely answers the question. The examples given are "a man of tact" and "a work of authority". But I cannot "be of tact" and a work cannot "be of authority". Conversely, if somebody can be of help, he is not "a man of help". Nov 5, 2011 at 17:25
  • The introduction to definition 41a states: ‘The quality . . . is often equivalent to an adjective as in “a man of tact” = a tactful man, “a work of authority” = an authoritative work.’ Similarly, ‘Please let me know whether I can be of help’ can be rewritten as ‘Please let me know whether I can be helpful (to you).’ Nov 5, 2011 at 18:18
  • 1
    You answered the part of the question about the meaning; the part of the question you didn't answer was "how to use them in different contexts". I should have been more specific. Nov 5, 2011 at 18:40
  • @PeterShor But we can't say "He is of a lot of help" but we can rightly say "He is of great help". I mean why is that? From your answer it is clear that not all noun can take part in "be of" construction, is there any restriction on the type of modifier an NP take in such construction? May 22, 2021 at 3:52

Not the answer you're looking for? Browse other questions tagged or ask your own question.