A clear, classroom‑ready reference with rules, meaning contrasts, verb patterns, and lots of examples + practice.

1) What they are (quick, friendly definitions)

Gerund = verb + -ing used as a noun.
- Swimming is fun. (subject)
- I enjoy reading. (object)
Infinitive = base verb, usually with to (the to‑infinitive) or sometimes without to (the bare infinitive).
- to read, to go, to be (to‑infinitive)
- can go, let me try (bare infinitive)
-ing ≠ always a gerund. In I’m reading, reading is a participle (part of the verb), not a noun.

2) Forms you can actually use

Gerund family

Simple: doing, going, being → I enjoy cooking.
Passive: being + past participle → She dislikes being interrupted.
Perfect: having + past participle → He admitted having lied (earlier action).
Perfect passive: having been + past participle → She regrets having been rude.

Infinitive family

Simple: to do / do → I hope to see you; You must see.
Continuous: to be + -ing → It’s nice to be working with you.
Perfect: to have + past participle → I’m sorry to have kept you waiting.
Passive: to be + past participle → It’s important to be heard.
Perfect passive: to have been + past participle → They’re delighted to have been invited.

Negation: use not: I decided not to go / I don’t mind not going.

3) Core rules at a glance (fast memory anchors)

After prepositions → Gerund
- I’m keen on learning; Thanks for helping; look forward to meeting
After most modals → Bare infinitive
- can/could/should/must/might/will/would + go
Adjectives → To‑infinitive (often with an impersonal it)
- It’s hard to explain; She’s ready to start
Purpose → To‑infinitive
- I called to ask a question.
Phrasal/preposition‑based expressions → Gerund
- be used to working, object to paying, the key to getting better

Exam tip: If there’s a preposition right before the gap (to, for, of, in, on, at, by, without, after, before, etc.), choose -ing.

4) Verb pattern map (by meaning)

Use this to predict the form after a verb.

A. Verbs typically followed by -ing

admit, avoid, can’t help, consider, delay, deny, dislike, enjoy, fancy, finish, give up, imagine, involve, keep (on), mind, miss, postpone/put off, practise, resent, risk, suggest

She admitted cheating.
They suggested meeting earlier.

B. Verbs typically followed by to‑infinitive

agree, aim, appear, arrange, ask, attempt, choose, decide, demand, expect, fail, help, hope, learn, manage, need, offer, plan, prepare, promise, refuse, seem, tend, threaten, want, would like/love/prefer

He decided to leave.
We hope to visit soon.

C. Object + to‑infinitive

advise, allow, ask, cause, enable, encourage, expect, forbid, force, get, invite, need, order, permit, persuade, remind, teach, tell, want, warn

They persuaded me to apply.
Please remind her to call.

D. Object + bare infinitive (no to)

let, make, (help) → Let me go; The film made me cry; This will help you (to) improve.

Passive of make adds to: I was made to wait.

E. Perception verbs (completed vs. ongoing)

see, hear, feel, notice, watch + object + bare infinitive (whole action) / object + -ing (action in progress)

I saw him cross the street (from start to finish)
I saw him crossing the street (in the middle of it)

F. Verbs that take either form with a change in meaning

stop + -ing = quit an activity: I stopped smoking
stop + to‑inf = stop in order to do sth else: I stopped to smoke
try + -ing = experiment/solution: Try restarting the router.
try + to‑inf = make an effort: I’m trying to study
remember / forget + -ing = recall/not recall past events: I remember meeting you.
remember / forget + to‑inf = don’t forget a task: Remember to lock the door.
regret + -ing = feel sorry about a past action: I regret saying that.
regret + to‑inf = formal announcement of bad news: We regret to inform you…
go on + -ing = continue same activity; go on + to‑inf = move to the next thing.
mean + -ing = involve: This job means working weekends.
mean + to‑inf = intend: I meant to call

G. Verbs that commonly take either (little or no real difference)

begin, start, continue, hate, like, love, prefer

It started to rain / raining. (both fine; -ing slightly more natural in speech)

H. “Passive‑like” -ing after need/require/want (BrE)

The car needs washing (= needs to be washed).
The windows require cleaning.

5) Prepositions & fixed phrases → -ing

After any preposition: after eating, without saying, by studying
Common “to” is a preposition phrases (so use -ing):
look forward to, be used to / get used to, object to, be opposed to, be committed to, in addition to, the key to
- I’m used to driving on the left.
- The key to getting fit is consistency.
Set expressions with but/except:
no/little/without choice but + to‑inf → We had no choice but to leave.
do nothing but + bare infinitive → He does nothing but complain.

6) Adjectives, nouns & question words with the infinitive

Adjective + to‑infinitive: easy/hard/nice/sad/ready/afraid/right/wrong → It was nice to meet you.
too/enough + to‑infinitive: too heavy to lift; warm enough to swim
Noun + to‑infinitive (ability/plan/decision/attempt/chance/way/time):
a chance to talk; a decision to postpone
wh‑ word + to‑infinitive (after verbs like ask/learn/decide/know/show/explain):
She taught me how to drive; I don’t know what to say

7) Style & syntax notes teachers love

Only the first verb is finite; following verbs are non‑finite (infinitive or -ing): I want to go / I enjoy going.
Possessive before gerunds (more formal): I disliked his arriving late (informal: him arriving).
Split infinitive (place adverbs carefully): to really understand is common and OK in most contexts.
Extraposition with “it” makes long subjects lighter: It’s important to arrive on time (vs To arrive on time is important).

8) High‑frequency error fixes (with better versions)

✗ I suggested to go → ✓ I suggested going / ✓ I suggested (that) we go.
✗ He recommended me to visit → ✓ He recommended visiting / ✓ He recommended (that) I visit.
✗ They made me to wait → ✓ They made me wait.
✗ I look forward to see you → ✓ … to seeing you.
✗ We must to finish → ✓ We must finish.
✗ I stopped to smoke (meaning quit) → ✓ I stopped smoking (quit). (stop to smoke = stop one action in order to smoke)

9) Micro “decision tree” (quick choosing guide)

Is there a preposition right before?
→ -ing (opposed to waiting; after eating; without saying)
Is there a modal (can, should, must, etc.)?
→ bare infinitive (must go, can wait)
Is it an adjective or purpose?
→ to‑infinitive (ready to start; to learn more, click…)
Which verb comes first? Check its pattern (see §4).
Meaning contrast verbs? (stop/try/remember/forget/regret/mean/go on) → choose based on meaning (see §4F).

10) Quick practice (with answers below)

Choose the correct form.

I can’t afford (buy / to buy / buying) a new laptop right now.
We look forward to (meet / to meet / meeting) you.
Please remind me (calling / to call / to calling) Marta.
I saw him (to cross / cross / crossing) the road from start to finish.
I stopped (to check / checking) the form because there was a mistake. (intended pause? choose accordingly)
Try (to restart / restarting) the router; it might fix it.
They made us (to wait / wait / waiting) outside.
She suggested (to go / going / go) by train.
It’s too late (calling / to call / for calling) now.
I regret (to say / saying) that we can’t accept the offer. (formal announcement? choose to say)
He’s used to (drive / to drive / driving) in snow.
The car needs (washing / to wash / to be wash).
We decided (go / to go / going) somewhere warm.
I heard them (to argue / argue / arguing) for a minute, then it went quiet. (whole action? bare; ongoing? arguing)
She told me (apply / to apply / applying) online.
Would you rather (to stay / stay) in or go out?
I’m not sure what (do / to do) next.
He continued (to talk / talking) for hours. (both acceptable)
We had no choice but (to leave / leaving).
I prefer (walking / to walk) to work, but I’d prefer (to take) a taxi today.

Answer key

1 to buy · 2 meeting · 3 to call · 4 cross (or crossing for ongoing) · 5 to check (pause)/checking (quit) · 6 restarting · 7 wait · 8 going · 9 to call · 10 to say (formal)/saying (past action) · 11 driving · 12 washing (BrE)/to be washed · 13 to go · 14 argue (completed)/arguing (in progress) · 15 to apply · 16 stay · 17 to do · 18 to talk / talking · 19 to leave · 20 walking, to take

11) Mini lists for classroom walls

-ing after prepositions: before/after/by/without/in/on/at/of/for/to → before going
Common adjective + to: easy/hard/ready/afraid/likely/unlikely/right/wrong/kind + (of + object) + to
Object + to‑inf verbs**:** allow/ask/encourage/expect/force/help/invite/order/permit/persuade/remind/teach/tell/want/warn
Bare infinitive: modals; let/make/(help); would rather / had better
Meaning‑switchers: stop/try/remember/forget/regret/mean/go on

Cheat Sheet (Visual Reference)

Quick Rules Flowchart

1. After a preposition? → -ing
(look forward to meeting, interested in learning)

2. After a modal verb (can, must, should, might, etc.)? → bare infinitive
(must go, can wait)

3. After an adjective (happy, hard, ready…)? → to-infinitive
(ready to start, hard to explain)

4. Purpose (why)? → to-infinitive
(I stopped to ask a question)

5. After these verbs? → check verb lists (see above)

Verb Pattern Map

➤ Verb + -ing

admit, avoid, consider, deny, dislike, enjoy, finish, give up, imagine, involve, keep (on), mind, miss, postpone, practise, risk, suggest

➤ Verb + to-infinitive

agree, appear, decide, expect, hope, learn, manage, need, offer, plan, promise, refuse, seem, tend, want, would like/love/prefer

➤ Verb + object + to-infinitive

advise, allow, ask, encourage, expect, force, invite, order, persuade, remind, teach, tell, want, warn

➤ Verb + object + bare infinitive

let, make, (help)

Verbs with Meaning Change

stop: quit (stop smoking) / purpose (stop to smoke)
try: experiment (try restarting) / effort (try to restart)
remember/forget: past (remember meeting) / task (remember to meet)
regret: past (regret saying) / formal news (regret to say)

Prepositions → -ing

after, before, by, without, in, on, at, of, for, to

Adjectives & Nouns → to-infinitive

It’s easy to learn, She’s ready to go, a chance to speak, too heavy to lift, what to say

Common Errors → Fixes

✗ suggested to go → ✓ suggested going
✗ recommended me to visit → ✓ recommended visiting
✗ made me to wait → ✓ made me wait
✗ look forward to see → ✓ look forward to seeing
✗ must to finish → ✓ must finish

Gerunds vs. Infinitives — Cheat Sheet

Use this simple, compact visual guide for learners, which is also comprehensive enough for teachers.