It's ridiculous (that) he couldn't solve the problem.
彼がその問題を解けなかったなんて，ばかな
It's ridiculous for a comedian to be without a sense of humor.
喜劇役者にユーモアの感覚がないとはあきれかえる
It's safe to say she's doing a great job.
彼女はよくやっていると言ってよい
It's simple - nothing fancy.
シンプルでまったくごてごてしていない
It's so hard for her to lose weight.
体重を落とすのは彼女にはとても難しい
It's so [unbearably, stiflingly] hot in here.
ここはとても［耐えられないほど，むっとして］暑い
It's still a long way from completion.
それはまだ完成には程遠い
It's strange that ....
…なのは不思議だ
It's such a performance cleaning it.
その掃除はとても大変だ
It's surprising.
それは驚いた
It's suspiciously cheap.
妙に安い
It's ten after eleven.
１１時１０分
It's the coffee.
コーヒーのせいだ（◆相手がなかなか寝つけないと言ったときなどに）
It's the done thing to do ....
…するのが決まり［常識］だ
It's the same issue in a different guise.
見かけこそ違うけれども同じ問題だ
It's the same old story [excuse].
よくある話［言い訳］だ
It's the same story here.
こっちも事情は同じだ
It's the same with many other foods.
そのことは他の多くの食べ物についても言える
It's the thought that counts.
大事なのは気持ちだ
It's the thought that counts.
((略式))（好意などが思ったような結果を出さなかったとき）大事なのは気持ちだから
It's the trouble with young people today.
それが今の若い人の問題だ（◆名詞の直後に置く）
It's the unbearable heat.
やりきれない暑さだ
It's thought he may have fallen.
彼は転倒したのかもしれないと考えられている
It's time to go back to work.
仕事に戻る時間だ
It's time to move on to the next step.
次の段階に進む時が来た
It's time to slow down a little.
少しゆっくりする時期だ
It's time you put the past behind you.
もう過去のことは忘れろよ
It's too early [late] in the day to stop it.
止めるには早すぎる［手遅れだ］
It's too early to say ....
…というのは時期尚早だ
It's too hard. No way can you do it.
難しすぎて出来るわけがない
It's unacceptable (for anyone) to commit an act of violence.
（だれも）暴力をふるうことは許されない
It's up to her to decide what to do next.
次に何をやるべきか決めるのは彼女しだいだ
It's very [highly] competitive to ask her out.
彼女をデートに誘うのはすごい競争だ
It's very hard to get that across to some people.
相手によってはそれをうまく伝えるのは非常に困難だ
It's very sweet of you.
どうもご親切に
It's vital to take action now to prevent this disease.
この病気の予防に今対処することが不可欠だ
It's warm enough to eat outdoors today.
今日は野外で食事できるぐらい暖かい
It's way too real for me.
それは私にはあまりにリアルすぎる
It's well funny.
ものすごくおもしろい
It's worth a go.
それはやってみる価値がある
It's your baby.
それはあなたの役目だ
It's your call.
((略式))それは君が決めることだよ
It's your chosen career.
それは君が好き好んで選んだ仕事だ
It's your go!
君の番だよ
It's your imagination.
気のせいだよ
It's your move!
君の番だ
It's your own doing.
それは君自身がしたことだ；身から出たさびだ
It's yours for the taking [the asking].
簡単に手に入る
It's「as simple as that [that simple].
（説明の最後で）それだけのことさ
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