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
