1. -Ing forms and infinitives

2. We use the -ing forms
Sometimes as a noun: Dancing is my favourite hobby.
After all prepositions, including particles of phrasal verbs: I learned to play the guitar by practising. I’ve given up smoking.
After certain expressions/prepositional phrases: I’m fed up with doing exams.
As the second part of a compound adjective: He’s very good-looking.

3. 1) -ing forms
After certain verbs: 1. Sarah enjoys going to school. 2. I’m considering going to college.
After prepositions: He’s looking forward to going to University. Is there any point in studying literature?
In certain expressions: It’s no good/use waiting. It’s not worth waiting. It’s a waste of time asking. I’m having difficulty/problems concentrating. We spend a lot of time revising.

4. 2. To-infinitive
After certain verbs/phrases: I want to study medicine. My friends taught me to swim. I can’t afford to go on holiday.
Agree, appear, arrange, ask, attempt, care, choose, decide, expect, …
After certain adjectives or nouns: It’s hard to learn language well. It’s my ambition to be a doctor.

5. 3. Bare infinitive After make/let: The teacher let me go home.
After certain expression: I’d rather not go. You’d better do your homework.
After most modal verbs: I might see you later.
(!!Be careful of ought to: We ought to leave now.)

6. 4. -ing form vs infinitive
I like to play/playing tennis on Saturday (specific situation) small change of meaning: begin, continue, start
A. I remember starting primary school (memory of a past event)
B. I must remember to do my homework tonight. (I mustn’t forget) Complete change in meaning: forget, go on, mean, regret, remember, stop, try
A. I heard my friend shout (completed action)
B. I heard my friend shouting (action in progress)