a: His dream is to go to Hollywood.

b: He is to go to Hollywood.

위 글에서

a:는 부정사가 명사로서 보어 역할을 하며

b:는 형용사로서 보어 역할을 하는 <be to> 용법이다.

구별하는 방법

주어=보어(His dream = to go to Hollywood)의 관계가  성립하면 명사적 용법(~것)

주어≠보어(he ≠ to go to Hollywood)이면 be to 용법

-be to 용법-

· He is to arrive here this evening.- 예정

· You are to observe the rules. - 의무

· You must work hard if you are to succeed- 의도

· He was never to return home. - 운명

· Only the priest was to go into the temple. -가능