VOA慢速英语:Bernanke Says Federal Reserve Will Act if US Economy Weakens

1.These include buying more securities in an effort to push down longer-term interest rates and increase economic growth.

push down向下按, 推倒, 压倒

例句：The criminal pushed a pedestrian down and ran away.
      罪犯推倒了一个行人逃跑了。

      The grass had been pushed down in places where people had been lying.
      人们躺过的那些地方, 草都被压倒了。

2.It followed a number of reports this week that added to concerns about the slow speed of recovery from the recession.

add to增加, 加强

例句：This lesson adds to the value of the book.
       这一课增加了这本书的价值。

      Since then, the palace has often been added to, rebuilt and repaired.
      从那以后, 那座宫殿不断得到扩建和修缮。

3.Not all the reports were bad.

Not all部分否定

all，every，both，always等用于否定结构时不是全部被否定，而是表示其中的一部分被否定。而且英语多半将not置于谓语中。

例如：

All is not a gold that glitters.（即Not all that glitters is gold.）
闪闪发光物，未必尽黄金。

Every one cannot write novels.（即Not every one can write novels.）
不是所有的人都能写小说。

I don’t like both of the novels.（即I like only one of the two novels.）
这两本小说我不是都喜欢。

4.And when people are scared, or are recovering from being scared, they don't necessarily run out and buy a house right away.

run out用完, 耗尽

例句：Our food soon ran out.
      我们的粮食很快就吃完了。

      He ran himself out in the first few circles.
      他才跑了几圈就没力气了。

not necessarily未必，不一定

例句：Freedom does not necessarily imply responsibility.
      自由不一定包含着责任。

      Clouds do not necessarily forecast rain.
      云层未必预示下雨。