You will always have the bad as well as the good in the world.

　　人生在世總是有苦有甜。

　　He has carried out extensive research into renewable energy sources.

　　他已經對再生能源進行了廣泛研究。

　　The first part of the plan has been safely accomplished.

　　計劃的第一部分已順利完成。

　　We had no say in the decision to sell the company.

　　在決定出售公司的問題上，我們沒有發(fā)言權。