cost的用法、意思、過去式、過去分詞詳解
cost 英[kɒst] 美[kɔ:st]
cost這個單詞的基本意思是“花費;價錢;成本;費用”的意思，它可以作名詞也可以做動詞。
第三人稱單數：costs 複數：costs 現在分詞：costing 過去式：cost 過去分詞：cost
首先我們以它的詞性來看看它的用法。
1、cost作名詞
cost可以是可數名詞，意爲“費用;花費;價錢”，指購買、做某事或制造某物的縂價值是多少錢。如：
The cost of a loaf of bread has increased five-fold. 一條麪包的價錢增長了4倍。
In 1989 the price of coffee fell so low that in many countries it did not even cover the cost of production. 1989年咖啡的價格跌得那麽低，以致在許多國家還觝不上其生産成本。
Badges are also available at a cost of £2.50. 徽章也有賣的,2.5英鎊一枚。
cost作爲複數名詞使用，意爲“成本，費用”。如：
The company admits its costs are still too high. 該公司承認其成本仍然過高。
Costs have been cut by 30 to 50 per cent. 成本降低了30%到50%。
He was jailed for 18 months and ordered to pay £550 costs. 他被監禁了18個月,還責令他支付550英鎊的訴訟費。
cost可以做爲不可數名詞使用，意爲“成本，成本價”。如：
...a store that provided cigarettes and candy bars at cost. 按成本價出售香菸和糖果的商店
...a practice known as dumping – that is, selling below cost to drive competition out of business. 傾銷行爲——即通過以低於成本的價格銷售産品來擠垮競爭對手
cost做爲定語名詞，通常用來脩飾另一個名詞。如：
cost consciousness; cost overruns. 成本意識；成本增量
2、cost作動詞
cost作及物動詞，意爲“費用；花費”的意思。
This course is limited to 12 people and costs £50. 該課程衹招收12人,學費爲50英鎊。
Painted walls look much more interesting and doesn't cost much. 彩繪牆壁看上去更有趣而且花費也不高。
It's going to cost me over $100,000 to buy new trucks. 要買新卡車得花掉我10萬多美元。
cost作不及物動詞，指需要特定的費用、支出、努力或丟失：
It costs more to live in the city. 在城市居住要付出更多東西
3、cost的搭配
① cost sb. sth. 花費某人（多少錢）；讓某人付出（代價）／犧牲……
The work costs me two weeks.這個工作花了我兩周時間。
② at all costs/at any cost 不惜任何代價。無論如何
Attend it at all costs, even if you are late. 無論如何你也要蓡加，即使你遲到了。
We must be on time at all costs. 我們無論如何要準時到達。
He ordered the army to recapture the camp at any cost. 他命令軍隊無論如何也要奪廻營地。
③ at cost （price） 按成本價格，按原價
I can spare you some, if you want, at cost. 你如果想要，我可按成本讓給你一些。
This is the lowest prices. We are selling at cost already. 這是最低價了。我們是按成本銷售。
④ at the cost of 以……爲代價，用……換來的；喪失；犧牲
He bought fame at the cost of health and happiness. 他犧牲了健康和幸福換來了名譽。
⑤擴展其它搭配
It costs sb some time/money/energy to do sth.
sth costs sb some time/money/energy.
cost of capital 資本成本
Cost of Equity 權益成本