Exercício: TOEFL Test - ''I have trouble remembering''

Eai galera,

Estou estuando TOEFL e me deparei com uma questão:

6. I have trouble _____.
a) to remember my password
b) to remembering my password
c )remember my password
d) remembering my password

A correta é a última, mas não sei porque a letra a) estaria errada. Quando que tenho que utilizar o verbo no gerúndio?
MENSAGEM PATROCINADA Faça um teste de inglês e descubra seu nível em 15 minutos! Este teste foi desenvolvido por professores e linguistas certificados. O resultado sai na hora e com gabarito.

Clique aqui para iniciar o Teste Online!
Avatar do usuário PPAULO 39165 6 32 684
After certain expressions you use gerund in the ING form, not the infinitive (with TO).
For more you can see in this handout.

ESLprof.com/handouts/Info/verb+gerund.doc

[Now you download it and save in your computer, or print it out and get it handy.]


As I said, the handout divide the verbs in "groups", that are:
1-Preference
2-Memory
3-stopping
4-Continuing
5-Thinking and Concentrating
6-Conversation
7-Being Careful
8-Delaying
9-Difficulty
10-Spending Time
11-Denial and Confession
12-Anticipation
13-Adapting
14-Activities; and
15-The "Lucky Seven" verbs can be followed by a gerund or an infinitive.
1. Continue 2. Start 3. Begin 4. Love 5. Like 6. Hate 7. Can't stand (=hate)



===================================================================================
Group 9: Difficulty
Subgroup 27. have trouble We had trouble finding a cheap hotel room there.

=====================================================================================



Hope it helps.
Avatar do usuário Donay Mendonça 49000 21 73 1137
Complemento:

Como disse o Paulo, há expressões que pedem o ING, e "have trouble" é uma delas. Há outras indicando "dificuldade" com a mesma característica:

Have difficulty remembering, etc.
Have problems remembering, etc.
Have a hard time remembering, etc.

= Ter dificuldade para lembrar, etc.

Dica do Longman Dictionary:

You can have problems doing something. Do not use 'to do'
• I'm having a problem finishing (NOT a problem to finish) this.
• He had problems finding (NOT problems to find) a job.
Thanks a lot guys! If I use the verb+ to it would be wrong?
Avatar do usuário PPAULO 39165 6 32 684
Yes, it would be wrong.
The handout is just to help students out with verbs that must finish in ING.
Thanks once!