表示“减少/变小”，常见的词语有decrease；表示“逐渐减少/变小”可用“dwindle/decline”；表示“迅速减少/变小”可用“plummet/plunge”；相关词组有“break down/come down/go down/head south”。具体见下文：

Decline

（1）作不及物动词时，常见搭配有：

decline by...

decline sharply/rapidly/dramatically

decline gradually/slightly/slowly

例句1：Milk production could decline by 15% or more in the late summer months. 去年夏天的产奶量可能减少了15%以上。

例句2：The party’s popularity has declined in the opinion polls. 民意调查结果显示该政党的支持率下降。

（2）作名词时，常见搭配有：

decline against

decline in

a rapid/sharp/steep/marked decline

a slight/slow/gradual/decline

例句：The housing industry experienced a decline in sales. 房产业销量下滑。

Decrease

（1）作动词时，既是及物动词也是不及物动词：

作不及物动词时，常见搭配有：

decrease in value/price/amount...

decrease by...

decrease significantly/dramatically/rapidly

decrease gradually/slightly/slowly

例句1：The tests show that the tumor has decreased in size since we started treatment. 化验结果显示，接受治疗以后，肿瘤变小了。

例句2：The country's total exports decreased by 6% in 2009. 2009年国家出口总额减少了6%。

例句3：Our share of the market has decreased sharply this year. 我们今年的市场份额大幅下滑。

作及物动词时：

例句：The company has introduced various strategies to decrease production costs. 公司尝试使用了各种策略减少生产成本。

（2）作名词时，常见搭配有：

decrease in value/price/amount...

decrease by...

decrease of

a marked/significant/dramatic decrease

a slight/gradual/steady decrease

例句1：When an investment increases or decreases in value but we do not sell it, we record an unrealized gain or loss. 投资减值但又不准备出售的，计入未实现损益。

例句2：There has been a steady decrease in the number of visitors. 游客数量稳步递减。

Dwindle

作不及物动词时，常见用法：

dwindle to sth.

dwindle from sth. to sth.

例句1：The community has dwindled to a tenth of its former size in the last two years. 在过去两年，该团体的规模仅有原来的十分之一。

例句2：The municipality’s population has dwindled from 40,000 to 24,000. 该市人口从40,000降至24,000。

引申：dwindling作形容词时，常见搭配：

dwindling number/population...

例句1：Companies are having recruitment difficulties as they battle it out for a dwindling number of skilled staff. 公司出现了招工难的问题，熟练工越来越少。

例句2：We are dealing with dwindling resources and aging buildings. 针对逐渐减少的资源以及陈旧的建筑物，我们正在想办法解决。

Plummet

（1）作不及物动词时：

例句：House prices have plummeted in recent months. 近几个月的房价暴跌。

（2）作名词时，常见搭配有：

plummet in

例句：The petrol retailer denies its 25% dividend hike is to prop up the shares after a plummet in the price from 270p to 118p. 汽油零售商否认股息上调25%是为了在股价从270p暴跌至118p之后推高股价。

Plunge

（1）作不及物动词时，常见搭配有：

plunge to sth.

plunge from sth. to sth.

plunge significantly/dramatically

例句1：The fall in demand caused share prices to plunge. 需求量下降导致股价暴跌。

例句2：Visitor numbers plunged from 25million in 2010 to 22.8million - but they are now recovering. 游客人数从2010年的2500万降至2280万，不过目前有所好转。

（2）作名词时，常见搭配有：

plunge in

例句：We are expecting a plunge in profits this year. 预计今年盈利暴跌。

Bring down

bring sth. down

例句：They’ve really brought down the price of laptops recently. 他们最近确实下调了笔记本电脑的价格。

Come down

例句1：We are expecting interest rate to come down. 预计利率可能会下降。

例句2：Sales went up and costs came down by about a third. 销售额增加，成本降低了大约三分之一。

Go down

go down (sth.) to sth.

例句：The temperature went down to minus ten last night. 昨晚气温降至零下十度。

Head south

例句：The job cuts followed significant drops in stock values when the Nasdaq headed south. 纳斯达克指数下跌，股价大幅下滑，紧接着就是裁员。