A. 不定詞の意味上の主語
  1. This kind of dance is one of the first ways for children to express their own feelings.
    cf. It is very kind of you to help me.
  2. Mr Brown found it important for his daughter to solve the problem by herself.
    (=Mr. Brown found it important that his daughter should solve the problem by herself.)
B. S + seem [appear, happen] + 不定詞
  1. Mary seems to be ill.
    (=It seems that Mary is ill.)
  2. Ballet dancers appear to resist gravity with their leaps.
  3. I happened to see a TV star near the station.
C. 対称の意味を表す接続詞while [where]
  1. While ballet dancers are trying to reach up to join God, in Nihon buyo, the music and dancing allow us to forget ourselves.
  2. Where ballet dancers resist gravity with their leaps, Nihon buyo dancers seem pulled down toward the Earth.