Why is "must admit to being" gramatically right?

[Torkoin]

English Language Proficiency Tests, Advanced Level

ESL/EFL Test #85 "Verbal Skills Test", question 5

I know you trust him but I have my doubts about him and must admit to being ......... of him.

(a) suspect
(b) suspecting
(c) suspicious
(d) suspected

English Language Proficiency Tests, Advanced Level

ESL/EFL Test #85 "Verbal Skills Test", answer 5

I know you trust him but I have my doubts about him and must admit to being suspicious of him.

Correct answer: (c) suspicious
_________________________

why is "must admit to being" gramatically right?

Torkoin

[Yankee]

Hi

I assume your basic question is why the word "being" (instead of "be") is correct.

The reason is that the word "to" is a preposition in this sentence and you need a gerund (the -ing form) after a prepostion. It is similar to the phrasal verb "look forward to":
"I look forward to seeing you."

Coming back to the test sentence, it is also possible to omit the prepositon "to" after the word "admit":
"I admit being suspicious of him."

(But it is not possible to omit "to" in the phrasal verb "look forward to")

Amy