Form:
If the root ends in a silent e, remove the e before adding -ing.
E.g. hoping (not hopeing), making (not makeing) and coming (not comeing).

Americans do not double a final unstressed letter L, but Britons and Canadians do.

Use:
Gerunds are hybrids. Strictly speaking, they are verbs, but they are used as nouns.
To form a gerund, take a base verb, e.g. go, eat, ski, make, be and add -ing to the end, creating going, eating, skiing, making and being.

Think of gerunds as being activities. As verbs, they can be the subject of a sentence
Smoking is addictive. Driving in rush hour takes guts. Playing golf relaxes me.

When activities are forbidden, we often use No + gerund :
No smoking, No loitering and No swimming.

Gerunds are not countable (never say a camping, a brainstorming, a parking, a planning, a smoking, a training or a towing ). They can, however, be used as noun modifiers: a camping site, a brainstorming session, a parking lot, a planning activity, a smoking room, a training manual or a towing station.

We often use them after a possessive adjective, such as my, your, John's, etc.
Does my smoking bother you? There is no excuse for your downloading
pornography on the office computer. Larry apologized for his arriving late.

This probably looks strange to you, but it is fairly common. Don't forget that gerunds are used as nouns, and we can possess nouns.

Not all words ending with -ing are gerunds.

Nouns can be identified by an article (the, a, an ) before them. They can be plural. E.g. a being, an opening, the buildings, a meeting, the feelings, a painting, the drawings, the ridings, the meaning, a misgiving, the reading, the computer settings.

Adjectives come before nouns: boring, deserving, enduring, fascinating, interesting.

Present participles are the -ing part of a progressive verb. They are identified by the auxiliary verb be in some form.
I am opening the car door.
The consultant has been training us all week.
Gerunds – Recreation

A common use of gerunds is after the verb go describe recreational activities. In these cases, go is conjugated appropriately. The closest French translation is faire du / de la ... or aller au / à la...

go bowling
go camping
go canoeing
go dancing
go fishing
go hiking
go hunting
go jogging
go kayaking
go mountain climbing
go running
go sailing
go shopping
go sightseeing
go skating
go skiing
go sledding
go snorkeling
go swimming
go tobogganing
go window shopping

Perhaps you don't consider all of these things to be recreation, but some people do. These are all possible to do alone.

Not all recreational activities take gerunds. Usually for team sports, we say play.
E.g. I play baseball, my sister plays volleyball and my brother plays hockey.
Golf can be spoken of either way.

Need + Doing

Another use of gerunds is in a passive structure using need. Remember, gerunds are activities.
E.g. This filing cabinet is ridiculous. It needs reorganizing.
My computer is ancient. It needs upgrading.
My hair is too long. It needs cutting.
My house is getting old. It needs renovating.
Our employees are falling behind in their knowledge. They need retraining.
Our company does things the old-fashioned way. It needs restructuring

Gerund Or Infinitive?

Some verbs can take either a gerund or an infinitive without a change in meaning (begin, continue, prefer, like, love, hate or start ). Mistakes are impossible, so it is not necessary to worry about them. However, some verbs mean one thing with a gerund and another with an infinitive:

stop + infinitive means s'arrêter pour. It explains the reason for something.
I stopped to smoke for a minute.

+ gerund means arrêter de.
I stopped smoking last month.

try + infinitive means have a project.
Jim tried to sleep.

+ gerund is used express multiple steps to accomplish that project.
Jim couldn't sleep. He tried counting sheep, drinking hot milk and reading a boring book. Nothing worked.

forget + infinitive is used for responsabilities.
Mario always forgets to take the garbage out.

+ gerund is used for everything else.
I forgot telling her that joke.

remember + infinitive is used for responsabilities.
Mario never remembers to take the garbage out.

+ gerund is used for everything else.
I remembered telling her that joke.

regret + infinitive is used for giving formal bad news. Sincerity is doubtful.
We regret to inform you that your application was refused.

+ gerund is used for everything else.
I regret admitting that to Helen. She told everyone.

Gerunds After Prepositions

These expressions also take gerunds, not infinitives. They can also be followed by a noun or a pronoun if the previous reference is clear. However, if a verb is used, it must be in the gerund form.

Notice that they end with prepositions. Whenever a verb follows a preposition (such as those used in phrasal verbs), it takes the gerund form. If a negative is used, not goes before the gerund. Don't be confused by to as a preposition. It can be part of an idiom.

about argue about something, care about something, complain about, dream about, forget about, talk about, think about

at stare at

at / in excel at/in

for apologize for, apply for something, blame someone for, care for someone, excuse someone for, fight for, forgive someone for, have a reason for,
have an excuse for, hope for, pray for, substitute for, thank someone for, vote for

from distinguish from, escape from, hide from, keep someone from,
prevent someone from, prohibit someone from, recover from, rescue from, stop someone from

in arrive in a vehicle, believe in, need practice in, participate in, succeed in

like feel like

of approve of, consist of, for the purpose of, have no intention of, instead of, take advantage of, take care of

on carry on, count on, depend on, decide on, go on, insist on, keep on, plan on, rely (up)on

to adjust to, apply to someone, contribute to, get used to, in addition to,
look forward to, introduce someone to, object to, respond to, subscribe to

to/with compare to/with

with agree with, argue with someone, provide with

Preposition Combinations of State

These expressions also take gerunds, not infinitives, but they are adjective expressions, always following the verb be. Remember, if a verb is used afterwards, it must be in a gerund form (-ing ).

about be confused about, be excited about, be worried about

against be discriminated against

at be good at, be surprised at

at/with be angry at/with

for be grateful for something, be known for, be prepared for, be qualified for,
be responsible for

from be absent from, be divorced from, be exhausted from, be gone from,
be protected from

in be dressed in, be engaged in something, be interested in, be involved in,
be located in, There is no point / use in

in/with be disappointed in/with

of be accused of, be afraid of, be aware of, be capable of, be composed of,
be connected to, be convinced of, be envious of, be fond of, be guilty of,
be in charge of, be innocent of, be jealous of, be little chance of, be proud of, be scared of, be terrified of, be tired of

of/by be frightened of/by

of/from be made of/from

to be accustomed to, be addicted to, be committed to, be dedicated to,
be devoted to, be engated to someone, be exposed to, be faithful to,
be grateful to someone, be limited to, be married to, be opposed to,
be polite to, be related to, be relevant to, be used to

to/with be friendly to/with

with be acquainted with, be associated with, be cluttered with, be content with, be covered with, be crowded with, be coordinated with, be done with,
be equipped with, be familiar with, be filled with, be finished with,
be furnished with, be patient with, be pleased with, be satisfied with

with / by be annoyed with/by, be blessed with/by, be bored with / by,
be upset with/by
Gerunds After Certain Verbs

Francophones have a natural tendency will be to use infinitives after these words (like in French). However, the following verbs and expressions are followed by gerunds, not infinitives. They can also be followed by a noun or a pronoun, if the previous reference is clear. However, if a verb is used, it must be in the gerund form. Remember that verbs can be conjugated in any verb tense.

Incorrect They enjoyed to watch that movie.
Correct They enjoyed watching that movie.

admit, anticipate, appreciate, avoid, can't help, can't stand, complete, consider, delay, deny, detest, discuss, dislike, enjoy, finish, imagine, involve, keep, mention, mind, miss, postpone, practice, propose, quit, recall, recollect, recommend, resent, resist, risk, suggest, tolerate, understand