thangvietnam wrote:
gerund, doing, can be used after a preposition/conjuction in the pattern
pre+doing+ main clause.
so the use of gerund after "decrease in" is ungrammatical
thangvietnamIn order to answer your query, I would have to first clarify that there are 2 types of gerunds:
First note that all gerunds are nouns. The two types of gerunds are as follows:
Simple gerund: Noun out, but verb inRaising the national flag on independence day is a norm in our school.
Here
raising is a simple gerund. If you look inside the phrase containing the gerund
raising the national flag, you would notice that the verb function is more prominent than the noun function; i.e. you could easily use the phrase as a full working verb:
I am raising the flag.Complex gerund: Noun out, noun in.The
raising of the rebel flag indicates the downfall of the regime.
Here
raising is a complex gerund. If you look inside the phrase containing the gerund
The raising of the rebel flag, you would notice that the noun function is more prominent than the verb function; i.e. you cannot easily use the phrase as a full working verb:
I am the raising of the rebel flag... senseless.
How to distinguish complex gerunds from simple gerunds? A complex gerund generally has an article, and in some cases an adjective, preceding it and a preposition after it. Following is an example from
MGMAT SC strategy guide:
Tracking satellites is important for space agencies: simple gerund.
The accurate
tracking of satellites is important for space agencies: complex gerund.
Now coming back to your query: usage such as
decrease in may be followed by a complex gerund ( noun out, noun in), but not a simple gerund (noun out verb in).
In the above example
demanding is a simple gerund and hence cannot be used after
decrease in.
However the following usage is correct:
There has been a decrease in the
spending of the consumers.
Here
spending is a complex gerund.
grammar books do not say enough of gerund and participle, or more exactly never say enough about DOING.
is a noun, not a gerund.
do you know the difference between the so called participle and gerund. I am not the winner of gmat but a failer of gmat.