It was a real challenge for us to go down the cliff on a rope.
私たちにとって、ロープで崖を降りるのは本当に大変でした。
I took a chance and accepted his challenge.
私はチャンスを掴み、彼の挑戦を受け入れました。
I intend to challenge him to a game.
彼にゲームを挑むつもりだ。
Thirdly, if you don't put in the effort and challenge difficult things, there is nothing in the world at which you will succeed.
第三に、努力して困難なことに挑戦しなければ、世界には成功するものは何もありません。
One of the important differences between Japanese and Americans is that Japanese tend to choose a safe course in life, while Americans choose to explore and challenge life.