By that time the new system should be up and running.

　　到那時(shí)這個(gè)新系統(tǒng)應(yīng)該會(huì)運(yùn)轉(zhuǎn)起來了。

　　Many people feel that the law should be changed.

　　許多人都覺得這項(xiàng)法律應(yīng)該修改。

　　The treatment should be repeated every two to three hours.

　　這種治療方法應(yīng)該每隔兩到三小時(shí)重復(fù)一次。

　　I think we should go back to first principles.

　　我認(rèn)為我們應(yīng)該回到基本原則上。

　　You should not go out in the heat of the day.

　　你不應(yīng)該在天最熱的時(shí)候外出。