发球是网球中最重要的击球。
"The serve is the most important shot in tennis."
可持续性不是一种选择——它是任何依赖自然资源的行业唯一的前进道路。
Over the piano was printed a notice: Please do not shoot the pianist. He is doing his best.
种一棵树最好的时间是20年前,第二好的时间是现在。