It is disappointing that they should have done such a thing.
彼らがそんなことをしたとはがっかりだ
It is doubtful that the missing child will ever be found.
その行方不明の子どもが見つかる見込みは薄い
It is doubtful whether [if] he will pass.
彼が合格するかどうか疑わしい
It is easily the best decision I have made in my life.
間違いなくこれまでで最良の決断だ
It is easy to make a man one's friend, but hard to keep him so.
友人をつくるのはたやすいが友情を保つのはむずかしい
It is easy to pronounce Italian.＝Italian is easy to pronounce.
イタリア語の発音はやさしい
It is enough for me to see you.
会えるだけで十分だ
It is entirely [particularly, highly] appropriate that ...
…ということはまったく［特に，きわめて］妥当だ
It is essential 「that you (should) do it yourself [for you to do it yourself].
自分でやるのが肝要である
It is extraordinary that he should not understand.
彼にわからないとはあきれたことだ
It is extremely small of you to even take that stance.
そんな態度までとるとは見下げたものだ
It is fitting for him to do so.＝It is fitting that he (should) do so.
彼がそうするのは適当だ
It is for you to decide whether or not you want to join a union.
君が組合に入りたいのかどうか決断すべきだ
It is frightening to think that he could be my boss.
彼が上司になるかもしれないと思うとぞっとする
It is futile to try to do so.
そうしようとしてもむだだ
It is generally agreed that pollution should be reduced.
汚染改善の一般的な合意がある
It is getting dark.
暗くなってきた
It is good practice to make backup copies.
バックアップを取っておくことはよい習慣だ
It is hard living [to live] in that city.
その町は住みにくい
It is hard to do two things at once.
１度に２つのことをするのは難しい
It is hardly possible that I can get there by six.
６時までにそこに着くのは不可能に近い
It is held to be good for the health.
それは健康によいと考えられている
It is highly desirable that you (should) get there by tomorrow.
明日までにそこに着くのが大変望ましい
It is highly improbable that she will marry him.
彼女が彼と結婚するなんてとうていありえない
It is highly unlikely that such an accident could occur.
そのような事故が起こることはとうていありえない
It is hopeless to continue trying to convince him.
彼に納得させようとし続けてもむだだ
It is I.
それは私です（◆((略式))では通例It's me. 詠嘆の表現などでもIの代わりにmeが用いられる：Dear m...
It is illegal to discriminate on the basis [grounds] of sex.
性差別は違法だ
It is illegal to do ...
…することは不法である
It is immediately obvious that ....
…ということはただちに明らかとなる
It is imperative 「that you (should) attend [for you to attend] the meeting.
その会議には必ず出席するように
It is important for him to do it.
彼がそれをやるのは重要だ（◆意味上の主語はforで示す）
It is important that exceptions (should) not be made.
例外を設けないことが大事だ
It is important to distinguish good from evil.
善悪のけじめをつけることが肝要だ
It is important 「for us to know [that we (should) know] the full truth.
我々にとって肝心なのは事実の全容を知ることだ
It is impossible of realization.
それは実現不可能だ
It is in your (best) interest(s) to study hard.
猛勉強が（一番）君のためだ
It is inconceivable that ...
…であるとはとても信じられない
It is incredible that he can't do that.
彼がそれをできないとは信じられない
It is incumbent on you to advise him.
彼に忠告するのは君の義務だ
It is interesting that no one noticed that mistake.
だれもその間違いに気づかなかったとはおもしろい
It is interesting to see ...
…を見るのはおもしろい
It is invisible to the naked eye.
それは裸眼では見えない
It is irrational to believe in magic.
魔術を信じるなんてばかげている
It is just 10 o'clock.
いまちょうど１０時です
It is just on six.
ちょうど６時です
It is kind of you to do ....
…してくださってありがとう
It is legitimate to ....
…するのも当然だ
It is little less than bribery.
収賄同然だ
It is mandatory to wear a seat belt.
シートベルトの着用は義務である
