281.Water, when boiled, always________ steam.

　　A) gives in

　　B) gives out

　　C) gives off

　　D) gives away

　　282.There are other problems which I don’t propose to________ at the moment.

　　A) go about

　　B) go into

　　C) to after

　　D) go in for

　　283.The farmers in this country can improve their________ by using better seedlings and more fertilizer.

　　A) yield

　　B) growth

　　C) harvest

　　D) gain

　　284.In addition to rice, we need to________ our diet with fish, meat and vegetable.

　　A) replace

　　B) supplement

　　C) replenish

　　D) mix

　　285.We had difficulties at first but everything worked________ smoothly in the end.

　　A) off

　　B) up

　　C) away

　　D) out

　　286.I didn’t like his offer so I turned it________ .

　　A) away

　　B) off

　　C) down

　　D) out

　　287.Be very careful with this ancient vase as it is________ a lot.

　　A) worthwhile

　　B) worth

　　C) worthy

　　D) deserving

　　288.Henry’s news report covering the conference was so________ that nothing had been omitted.

　　A) comprehensive

　　B) inclusive

　　C) concise

　　D) precise.

　　289.As a________ president, his views are treated with respect when he is interviewed.

　　A) prior

　　B) previous

　　C) late

　　D) former

　　290.After considering various alternatives, we decided to________ our original plan.

　　A) hang on

　　B) hold to

　　C) take to

　　D) see to

　　291.The supply of electric power to the city and its neighboring districts has had to be________ .

　　A) weakened

　　B) minimized

　　C) restricted

　　D) slowed

　　292.I cut my finger two days ago and it has become badly________ .

　　A) infected

　　B) decayed

　　C) deteriorated

　　D) diseased

　　293.Is it advisable to________ our body to the sunlight?

　　A) reveal

　　B) display

　　C) expose

　　D) show

　　294.She has to be very________ because she hasn’t much money.

　　A) economic

　　B) economical

　　C) sparing

　　D) careful

　　295.John was so________ in his book that he did not hear the door bell ring.

　　A) engaged

　　B) occupied

　　C) absorbed

　　D) concentrated

　　296.I helped him clean the floor________ the understanding that I would be rewarded.

　　A) through

　　B) by

　　C) in

　　D) on

　　297.Don’t________ this news to the public until we give you the go-ahead.

　　A) release

　　B) relieve

　　C) relate

　　D) inform

　　298.What you have done is________ the doctor’s orders.

　　A) subject to

　　B) opposite

　　C) resistant to

　　D) contrary to

　　299.Your failure in the final examination is due to the fact that you didn’t________________enough importance to your English.

　　A) put

　　B) attach

　　C) render

　　D) place

　　300.When we finally________ to get home after the tiring long journey, we could hardly move a step further.

　　A) tried

　　B) succeeded

　　C) managed

　　D) endeavoured