A gerund is a verb form that ends in -ing and is used as a noun: sleeping, dreaming. An infinitive is the word to plus the base form of the verb: to sleep, to dream. The word to is an infinitive marker, not a preposition, in this use. (See B3-b.)
A few verbs may be followed by either a gerund or an infinitive; others may be followed by a gerund but not by an infinitive; still others may be followed by an infinitive but not by a gerund.
Verb + gerund or infinitive (no change in meaning)
The following commonly used verbs may be followed by a gerund or an infinitive, with little or no difference in meaning:
begin | like |
continue | love |
hate | start |
I love skiing. I love to ski.
Verb + gerund or infinitive (change in meaning)
With a few verbs, the choice of a gerund or an infinitive changes the meaning dramatically:
forget |
remember |
stop |
try |
She stopped speaking to Lucia. [She no longer spoke to Lucia.]
She stopped to speak to Lucia. [She paused so that she could speak to Lucia.]
Verb + gerund
These verbs may be followed by a gerund but not by an infinitive:
admit | finish | quit |
appreciate | imagine | recall |
avoid | miss | resist |
deny | postpone | risk |
discuss | practice | suggest |
enjoy | put off | tolerate |
escape |
Bill enjoys playing [not to play] the piano.
Jamie quit smoking.
Verb + infinitive
These verbs may be followed by an infinitive but not by a gerund:
agree | hope | promise |
ask | manage | refuse |
beg | mean | wait |
claim | need | want |
decide | offer | wish |
expect | plan | would like |
help | pretend |
Jill has offered to water [not watering] the plants while we are away.
Joe finally managed to find a parking space.
A few of these verbs may be followed either by an infinitive directly or by a noun or pronoun plus an infinitive:
ask | help | promise | would like |
expect | need | want |
We asked to speak to the congregation.
We asked Rabbi Abrams to speak to our congregation.
Verb + noun or pronoun + infinitive
With certain verbs in the active voice, a noun or pronoun must come between the verb and the infinitive that follows it. The noun or pronoun usually names a person who is affected by the action of the verb.
advise | convince | order | tell |
allow | encourage | persuade | urge |
cause | have (“own”) | remind | warn |
command | instruct | require |
The counselor advised Haley to take four courses instead of five.
Verb + noun or pronoun + unmarked infinitive
An unmarked infinitive is an infinitive without to. A few verbs (often called causative verbs) may be followed by a noun or pronoun and an unmarked infinitive.
have (“cause”) | let (“allow”) |
help | make (“force”) |
Help can be followed by a noun or pronoun and either an unmarked or a marked infinitive.
Emma helped Brian wash the dishes.
Emma helped Brian to wash the dishes.
note: The infinitive is used in some typical constructions with too and enough.
too + adjective + infinitive
The gift is too large to wrap.
enough + noun + infinitive
Our emergency pack has enough bottled water to last a week.
adjective + enough + infinitive
Some of the hikers felt strong enough to climb another thousand feet.