Being in an unfamiliar city can be frightening. 置身于一个不熟悉的城市里可能是件令人害怕的事. Traveling long distances by train can be tiring.坐火车长途旅行可能很累人. Study hard is rewarding. 用功读书是有好处的. Climbing mountains is very exciting. 爬山是很刺激的. You may find it difficult to follow what they're saying. 你也许会发现要了解他们的话很困难. Mary find her new job a challenge. 玛丽发现她的新工作是项挑战. I thought the job very easy. 我以为这个工作非常简单. I think it rude to interrupt. 我认为打断别人的话是很粗鲁的.