Verbs after adjectives and prepositions
Young children often feel shy to talk to adults. (incorrect)Young children often feel shy talking to adults. (correct)
It is easy to understand why. (correct)
It is easy understanding why. (incorrect)
With feel + adjective we use the -ing form of the verb:
New students do not always feel comfortable speaking English to other people.
After be + adjective, too + adjective and adjective + enough, we use to + infinitive:
I was happy to see her when she arrived. (not I was happy seeing her)
The lecture was easy enough to understand. (not enough easy or easy understanding)
After all prepositions (about, by, from, for, in, of, without, etc.) we use the -ing form of the verb; we cannot use a clause (subject + verb):
They celebrated their anniversary by organising a big party.
Thank you for helping me so much with my studies.
He opened the door without thinking about what would happen next. (not without he thought)
Note that despite, in spite of and instead of are considered to be prepositions:
He did not get the job despite getting excellent grades. (not despite he got)
She went to the library instead of going straight home after school. (not instead of she went)
If the following verb is negative, we use not + -ing
He got a job despite not getting good grades. See more IELTS common mistakes