The Infinitive with to

after: the first Gagarin was the first to fly in a spaceship.
the last Peter was the last to watch the film.
the next He is the next to get his passport.

 
after: adjectives I'm happy to be here.
It's better not to smoke.

 
after: certain verbs
(agree, choose, forget, hope, learn, promise, regret, want, …)
I learn to drive a car.

 
after: question words I don't know what to say.
Can you tell me how to get to the bus stop?

 
after: want/would like I want you to help me.

 
verb + object + to-infinitive I helped my dad to clean the car.
I want to help you. I want you to help me.