Prepositions in English display a powerful diversity of uses. In previous preposition article, we talked about the proposition "to". Here, we will look, at the preposition "of."
The preposition "of"
The word "of" is a preposition. This means, it must be followed by a noun --- or by something playing the role of a noun. This latter category includes gerunds and substantive clauses.
1) No amount of talking about issues facing the homeless will satisfy their most basic needs in the short term.
2) We are now absorbing the unfortunate consequences of what last year's county administration thought would benefit us all.
In sentence #1, the object of the preposition “of” is a gerund phrase, and in sentence #2, the object is a substantive clause. Incidentally, both of these are exemplary of idioms involving the word “of.”
Verbs requiring "of"
There are three very different verb idioms involving "of":
accuse A of B
think of A as B
In the idiom "A consists of B", A is the complete object or the finished product, and B is the material of which this product is composed. It can be used literally, for the actual physical material making up an object, or it can be used metaphorically for the content of something.
3) Atomic Theory states that all material objects consist of atoms and that the macroscopic properties of objects depend on the microscopic interactions of these atoms.
4) The candidate argued that his opponent's "New Horizons" program consisted of no more than a revision of the former governor's discredited ideas.
Notice that, idiomatically, we would use the present participle for this verb, "consisting of", but the past participle for two verbs with the same meaning: "made of" and "composed of."
Now, a totally different idiom. When someone accuses A of B, A is the person accused, and B is the crime or infraction.
5) Javert accused Valjean of various crimes.
6) The Inquisition never formally accused Galileo of heresy, only finding him "vehemently suspect of heresy."
The final idiom is particularly difficult: think of A as B. Here, A is the person or thing under consideration, and B is a role or a rank or a metaphor for A.
7) I think of my friend Chris as a walking dictionary and thesaurus.
8) Many Chinese think of Li Bai as the single greatest poet in their three-thousand year old civilization.
9) Some feminists think of chivalry as an outmoded set of behaviors and values that, despite their patina of gentility, promote damaging gender inequities.
10) Fundamentalist Christians in the US think of Evolution as merely an opinion held by some scientists, whereas most scientists writing in peer-reviewed journals think of it as established truth beyond any doubt.
A potpourri of idioms
The diversity of idioms involving "of" is mind-boggling. One collection has to do with the composition or constituency of things:
a collection of
a number of
an amount of
The first three were discussed in the previous section. Most other collective nouns (organization, association, crowd, team, herd, flock, etc.) follow this pattern. The object of the preposition "of" are the people or items or material that compose the group or the whole. Remember to use "number" for things you can count, and "amount" for uncountable bulk.
11) A large number of coal miners develop pneumoconiosis.
12) The amount of revenue that the United States government collects from payroll taxes in the US is approximately equal to the amount of revenue from personal income taxes.
Another closely related idiom:
When we speak of a "chance of A" or a "probability of A", A is the event whose probability we are discussing. This event A may be an ordinary noun, or even a gerund or gerund phrase, but the GMAT does not like the construction
If you want to talk about that much action, you need a full "that" clause with a [noun] + [verb]. Don't try to wedge a full action into a preposition phrase using a noun & a participial phrase: chance that or probability that
13) On a five card draw from a full deck, the chance of drawing a "royal flush" is 649,740 to 1.
14) The probability that a player will hit four homeruns in a single baseball game is very low: this feat has happened only sixteen times in the history of Major League Baseball.
If this last sentence had been phrased "The probability of a playing hitting …", that would be the form to which the GMAT objects.
One idiom metaphorically related to the "constituency" idiom above is:
Here, when we say A is capable of B, A is the person and B is an action. Metaphorically, A "contains" or "is made of" the capacity to do B. Often, this plain statement, "A is capable of B", can be rephrased more concisely using "can." Nevertheless, this flexible idiom can appear in a number of other guises:
15) The detective considered the culprit capable of cold-blooded murder.
16) The swan, capable of flying long distances, is much more frequently depicted on water than in the air.
Two words follow a very different idiom with "of"
Whether we say A is a result of B or A is a consequence of B, we are saying B is the cause and A is the effect.
17) Skin cancer is often the result of many years of sunbathing.
18) Unemployment is often an unintended consequence of raising interest rates.
Once again, it's fine to have a gerund or gerund phrase, but if the case involves both a noun and a verb, we could no longer use the preposition "of" --- we would have to change around the entire sentence.
Many prepositions consist of only one word, but in a few instances, two words together function as a single preposition. Four of these involve "of":
For the first two, again it is important to remember: a preposition can have as its object either an ordinary noun or (more likely on the GMAT) a gerund phrase, but if we want to put a full noun + action phrase, the GMAT frowns on having a [noun] + [participle] follow a preposition. This latter structure demands a full subordinate clause. In fact, this is precisely the difference between "because of" and "because."
19) Because of the uncertainty surround the new tax law being debated in Congress, the stocks dropped for a third consecutive day.
20) Instead of invading the Italian peninsula by sea, as all previous aggressors had done, Hannibal travelled over the Alps to invade by land from the north.
The idiom "as of" is particular tricky: it is used to denote the precise time of a particular transition. The object of "as of" is always either a time or an event whose time is well known.
21) As of next Wednesday, Phophon Stores will no longer accept the competitor's coupons.
22) As of the enactment of the 26th Amendment in June, 1971, all citizens between the ages of 18 and 21 have been eligible to vote in all elections.
The idiom out of can be used for the physical movement from a place ---- think of Isak Dinesen's memoir Out of Africa --- but more often it is used metaphorically for the source material of some creation:
23) Out of innumerable Slavic folk melodies, Tchaikovsky fashioned some of the finest masterpieces of the classical repertoire.
24) Out of the seemingly intractable contradictions between Newtonian and Maxwellian physics, Einstein created the Theory of Relativity.
Three special combination idioms
Finally, here are three particular combinations of terms with prepositions that you need to know:
in danger of
in violation of
on account of
In the idiom in danger of A, A is some penalty or unfortunate consequence.
25) The sophomore who hosted all the keg parties was in danger of failing all of his classes.
26) If the government of Greece defaults on its national loans, the country will be in danger of losing its Eurozone membership.
In the idiom in violation of A, A is the law or principle that the agent is violating.
27) Republicans have argued that the PPACA is in violation of the Commerce Clause.
28) The cultural critic pointed out that the behavior depicted on prime-time television is in violation of most of the Commandments.
29) In Euclidean Geometry, a triangle whose angles had a sum other than 180° would be in violation of the Parallel Postulate.
Finally, a very tricky case: the idiom on account of is roughly synonymous to the idiom because of. The latter is more natural in most cases, and usually lends itself to a more concise phrasing. The former is more pretentious and verbose, which makes it appropriate, say, for legal-ese, but not particularly appropriate for the GMAT.
30a) On account of the stock market's sudden and precipitous rise, the bond market has rallied over the past few days.
30b) Because of the stock market's sudden and precipitous rise, the bond market has rallied over the past few days.
Technically, both versions of the previous sentence are correct. Nevertheless, I have never seen the idiom "on account of" part of a correct answer on the GMAT Sentence Correction. On the one hand, be suspicious if you see Sentence Correct answer choices involving "on account of", but on the other hand, know that it is technically correct.
Know the idioms given in bold in this post. As always with idioms, read, read, read! Search for the idioms in this post in context. You understand English best when you understand it in context.
This post was written by Mike McGarry, GMAT expert at Magoosh, and originally posted here.