Spend . Expend . Cost . Pay

以上四个词和“消费”、“花费”和“消耗”有关。

●首先，spend主要做及物动词使用，其宾语可以是“钱”、“时间”或“精力”。

Every year, she spends a lot of money on clothes.

女孩，您用生命买衣服啊。

We’ve just spent 1.9 million on improving our computer network.

笔者回想起在老东家有一段时期几十个电脑共享1MB带宽的工作环境，何其辛苦！

I’ve spent an hour in the station waiting for the train.

各位瞅仔细了，spend [money] on doing sth.但是spend [time] doing sth.这就是区别。雅思()考官各个鹰眼犀利，可别范怂。

My sister always spends ages in the bathroom.

我姐姐洗澡总是洗很久很久。

I want to live in a dormitory to spend time with my school friends.

For the past month, he’s spending all the energy trying to find a job.

此外，spend并非大家想象的只能由人或机构做主语：

Her anger soon spent itself (=stopped). 她只生了一会气。

●expend的用法和spend差不多，比expend更为正式，可以用于雅思写作；

You expend so much effort for so little return.

你还真是入不敷出。

Governments expend a lot of resources on war.

政府在战争上投入很多资源。

●cost的用法与spend, expend不同。cost的主语一般是花出去的钱、时间和精力的对象。

I cost 30 dollars for the board game. X

The board game costs me 30 dollars.√

I spend 30 dollars for the board game.√

One costs more money running a business than buying a house. X

Running a business costs more money than buying a house.√

It costs more money to run a business than to buy a house.√

（因为这句话的主语是不定式to run a business，所以它被放在谓语和宾语后面，主语用it代替）

●pay的用法。pay强调“付款”，也有pay [money] for sth.这样一看就懂的用法

You have to pay four dollars for each hamburger.

当然pay还有很多其他用法。

Mum paid for my driving lessons./Mum paid me for the driving lessons.

妈妈帮我付了学开车的钱。

Ray paid some kids to wash his car.

Ray花钱叫几个小孩来洗他的车。

Ray paid the kids 10 dollars to wash his car.

Ray花10美元叫这孩子洗他车。

A savings plan that paid six percent interest

一个6%利息的储蓄方案

It pays to be honest. (= It is good to be honest)

William is now paying the price for his early mistakes.

威廉姆现在在为他之前的错误买单。

I decide to pay my folks a visit this weekend.