Gerunds

A kind of verbal noun, having only the four oblique cases of the singular number, and governing cases like a participle. (AS. Gram.) A verbal noun ending in -e, preceded by to and usually denoting purpose or end; -- called also the dative infinitive; as, “Ic hæbbe mete tô etanne” (I have meat to eat.) In Modern English the name has been applied to verbal or participal nouns in -ing denoting a transitive action; e. g., by throwing a stone.

the gerund is identical in form to the present participle (ending in -ing) and can behave as a verb within a clause (so that it may be modified by an adverb or have an object), but the clause as a whole (sometimes consisting of only one word, the gerund itself) acts as a noun within the larger sentence. For example: Eating this cake is easy.

In "Eating this cake is easy," "eating this cake," although traditionally known as a phrase, is referred to as a non-finite clause in modern linguistics. "Eating" is the verb in the clause, while "this cake" is the object of the verb. "Eating this cake" acts as a noun phrase within the sentence as a whole, though; the subject of the sentence is the non-finite clause, specifically eating.
Other examples of the gerund:

• I like swimming. (direct object)
• Swimming is fun. (subject)

Not all nouns that are identical in form to the present participle are gerunds.^[3] The formal distinction is that a gerund is a verbal noun – a noun derived from a verb that retains verb characteristics, that functions simultaneously as a noun and a verb, while other nouns in the form of the present participle (ending in -ing) are deverbal nouns, which function as common nouns, not as verbs at all. Compare:

• I like fencing. (gerund, an activity, could be replaced with "to fence")
• The white fencing adds to the character of the neighborhood. (deverbal, could be replaced with an object such as "bench")

Double nature of the gerund

As the result of its origin and development the gerund has nominal and verbal properties. The nominal characteristics of the gerund are as follows:

1. The gerund can perform the function of subject, object and predicative:
   • Smoking endangers your health. (subject)
   • I like making people happy. (object)
2. The gerund can be preceded by a preposition:
   • I'm tired of arguing.
3. Like a noun the gerund can be modified by a noun in the possessive case, a possessive adjective, or an adjective:
   • I wonder at John's keeping calm.
   • Is there any objection to my seeing her?
   • Brisk walking relieves stress.

The verbal characteristics of the gerund include the following:

1. The gerund of transitive verbs can take a direct object:
   • I've made good progress in speaking Basque.
2. The gerund can be modified by an adverb:
   • Breathing deeply helps you to calm down.
3. The gerund has the distinctions of aspect and voice.
   • Having read the book once before makes me more prepared.
   • Being deceived can make someone feel angry.

Verb patterns with the gerund

Verbs that are often followed by a gerund include admit, adore, anticipate, appreciate, avoid, carry on, consider, contemplate, delay, deny, describe, detest, dislike, enjoy, escape, fancy, feel, finish, give, hear, imagine, include, justify, listen to, mention, mind, miss, notice, observe, perceive, postpone, practice, quit, recall, report, resent, resume, risk, see, sense, sleep, stop, suggest, tolerate and watch. Additionally, prepositions are often followed by a gerund.
For example:

• I will never quit smoking.
• We postponed making any decision.
• After two years of deciding, we finally made a decision.
• We heard whispering.
• They denied having avoided me.
• He talked me into coming to the party.
• They frightened her out of voicing her opinion.

Verbs followed by a gerund or a to-infinitive

With little change in meaning

advise, recommend and forbid:
These are followed by a to-infinitive when there is an object as well, but by a gerund otherwise.

• The police advised us not to enter the building, for a murder had occurred. (Us is the object of advised.)
• The police advised against our entering the building. (Our is used for the gerund entering.)

consider, contemplate and recommend:
These verbs are followed by a to-infinitive only in the passive or with an object pronoun.

• People consider her to be the best. – She is considered to be the best.
• I am considering sleeping over, if you do not mind.

begin, continue, start; hate, like, love, prefer
With would, the verbs hate, like, love, and prefer are usually followed by the to-infinitive.

• I would like to work there. (more usual than working)

When talking about sports, there is usually a difference in meaning between the infinitive and gerund (see the next section).

With a change in meaning

like, love, prefer
In some contexts, following these verbs with a to-infinitive when the subject of the first verb is the subject of the second verb provides more clarity than a gerund.

• I like to box. (I enjoy doing it myself.)
• I like boxing. (Either I enjoy watching it, I enjoy doing it myself, or the idea of boxing is otherwise appealing.)
• I do not like gambling, but I do like to gamble."

dread, hate and cannot bear:
These verbs are followed by a to-infinitive when talking subjunctively (often when using to think), but by a gerund when talking about general dislikes.

• I dread / hate to think what she will do.
• I dread / hate seeing him.
• I cannot bear to see you suffer like this. (You are suffering now.)
• I cannot bear being pushed around in crowds. (I never like that.)

forget and remember:
When these have meanings that are used to talk about the future from the given time, the to-infinitive is used, but when looking back in time, the gerund.

• She forgot to tell me her plans. (She did not tell me, although she should have.)
• She forgot telling me her plans. (She told me, but then forgot having done so.)
• I remembered to go to work. (I remembered that I needed to go to work.)
• I remembered going to work. (I remembered that I went to work.)

go on:

• After winning the semi-finals, he went on to play in the finals. (He completed the semi-finals and later played in the finals.)
• He went on giggling, not having noticed the teacher enter. (He continued doing so.)

mean:

• I did not mean to scare you off. (I did not intend to scare you off.)
• Taking a new job in the city meant leaving behind her familiar surroundings. (If she took the job, she would have to leave behind her familiar surroundings.)

regret:

• We regret to inform you that you have failed your exam. (polite or formal form of apology)
• I very much regret saying what I said. (I wish that I had not said that.)

try:
When a to-infinitive is used, the subject is shown to make an effort at something, attempt or endeavor to do something. If a gerund is used, the subject is shown to attempt to do something in testing to see what might happen.

• Please try to remember to post my letter.
• I have tried being stern, but to no avail.

stop, quit:
When the infinitive is used after 'stop' or 'quit', it means that the subject stops one activity and starts the activity indicated by the infinitive. If the gerund is used, it means that the subject stops the activity indicated by the gerund.

• She stopped to smell the flowers.
• She stopped smelling the flowers.

Or more concisely:

• She stopped walking to smell the flowers.

• He quit working there to travel abroad.

Gerunds preceded by a genitive

Because of its noun properties, the genitive (possessive case) is preferred for a noun or pronoun preceding a gerund.

• We enjoyed their [genitive] singing.

This usage is preferred in formal writing or speaking. The objective case is often used in place of the possessive, especially in casual situations:

• I do not see it making any difference.

Really, 'I do not see its making any difference' is the correct option.
This may sound awkward in general use, but is still the correct manner in which to converse or write. And this form of gerund is applicable in all relative cases, for instance:

• He affected my going there.
• He affected your going there.
• He affected his/her/its going there.
• He affected our going there.
• He affected their going there.

This is because the action, of doing or being, belongs, in effect, to the subject/object (direct or indirect) practising it, thus, the possessive is required to clearly demonstrate that.
In some cases, either the possessive or the objective case may be logical:

• The teacher's shouting startled the student. (Shouting is a gerund, and teacher's is a possessive noun. The shouting is the subject of the sentence.)
• The teacher shouting startled the student. (Shouting is a participle describing the teacher. This sentence means The teacher who was shouting startled the student. In this sentence, the subject is the teacher herself.)

Either of these sentences could mean that the student was startled because the teacher was shouting.
Using the objective case can be awkward, if the gerund is singular but the other noun is plural. It can look like a problem with subject-verb agreement:

• The politicians' debating was interesting.

One might decide to make was plural so that debating can be a participle.

• The politicians debating were interesting.

Gerunds and present participles

Insofar as there is a distinction between gerunds and present participles, it is generally fairly clear which is which; a gerund or participle that is the subject or object of a preposition is a gerund, if it refers to the performance of an action (but present participles may be used substantively to refer to the performer of an action), while one that modifies a noun attributively or absolutely is a participle. The main source of potential ambiguity is when a gerund-participle follows a verb; in this case, it may be seen either as a predicate adjective (in which case it is a participle), or as a direct object or predicate nominative (in either of which cases it is a gerund). In this case, a few transformations can help distinguish them. In the table that follows, ungrammatical sentences are marked with asterisks, per common linguistic practice; it should be noted that the transformations all produce grammatical sentences with similar meanings when applied to sentences with gerunds but either ungrammatical sentences, or sentences with completely different meanings, when applied to sentences with participles.

source:
http://dictionary.sensagent.com/gerunds/en-en/
http://en.wikipedia.org/wiki/Gerund