1.有时表语可用不定式表示：
Her aim was to do two years work in one.
她的目标是一年干两年的工作。
My job is to type letters.
我的工作是打信。
My only wish is to do what's best for you.
我唯一的愿望是做对你最好的事。
His strategy is to win the war with air power.
他的战略是以空军制胜。
My advice to you is to speak the truth.
我对你的忠告是说真话。
But worse was to follow.
但更坏的情况还在后头。
2.有时不定式可用被动形式：
Some books are to be read for pleasure.
有些书是看着玩的。
That's not to be taken too seriously.
这不可看得太认真。
These pills are to be taken three times a day after meals.
这些药丸每天吃二次，饭后吃。
Surely she was to be trusted.
她肯定是值得信任的。
3.有时主语和表语都用不定式表示：
To do that is to ruin yourself.
这样做是毁掉你自己。
To do this is to cut the foot to fit the shoe.
这样做是削足适履。
To see is to believe.
眼见为实。
4.有的表语可以用动名词表示：
One of my weaknesses is smoking too much.
我的缺点之一是抽烟太多。
Our problem is not having sufficient raw material.
我们的问题是原料不足。
His job is tuning the piano.
他的任务是给钢琴调音。
Her hobby is collecting stamps.
她的爱好是集邮。
5.有时主语和表语都用动名词表示：
Doing that would be playing with fire.
那样做是玩火。
Seeing is believing.
眼见为实。
Buying such a white elephant is simply wasting money.
买这样大而无用的东西完全是浪费金钱。
