51. In the experiment we kept a watchful eye _D_ the developments and recorded every detail. [keep a watchful eye on 密切主意，留神]
A in B at C for D on
52. There's little chance that mankind would _D_ a nuclear war.
A retain B endure C maintain D survive
retain vt. 保持，保留； endure v. 忍受； maintain vt. 維持，保持，堅持認為；
survive vi. 生存； vt. 活過 … （賓語為某種災(zāi)難）。 survive a flood 活過一場洪水。
前綴sur表示過 … ，外，超； vive 表示生活，強調(diào)活著。
54. They usually have less money at the end of the month than _C_ at the beginning.
A which is B which was C they have D it is
less … than句子前后要平衡結(jié)構(gòu)。
55. In the course of a day students do far more than just _A_ classes.
A attend B attended C to attend D attending
far more than 遠遠多于，遠不止于；也要句子前后平衡結(jié)構(gòu)。
56. The French pianist [n. 鋼琴師] who had been praised very highly _C_ to be a great disappointment.
A turned up B turned in C turned out D turned down
turn up 后面不加賓語表示出現(xiàn)，后面加賓語表示將聲音調(diào)高，調(diào)大；
turn in + 賓語 上繳，交出； turn down 將聲音調(diào)低，調(diào)?。痪芙^；
refuse sb. 指直接的回絕； turn sb. down 則指委婉的拒絕；
turn out + 動詞不定式 最終證明是，結(jié)果是。
57. Many difficulties have _B_ as a result of the change over to a new type of fuel.
A risen B arisen C raised D arrived
因本句未加賓語，估不應(yīng)選不及物動詞，可排除C項； arrive vi. 到達，抵達；
rise vi. 升起，升高（側(cè)重指旗幟或太陽升起）；數(shù)量的增高（側(cè)重指水位、價位）；
the sun rises in the east and sets in the west 太陽東升西落。
arise vi. 升起，升高，出現(xiàn)，發(fā)生（經(jīng)常與抽象名詞聯(lián)用）。
69. A completely new situation will _B_ when the examination system comes into existence.
A arise B rise C raise D arouse
33. Last year the advertising rate _D_ by 20 percent.
A raised B aroused C arose D rose
58. He made such a _D_ contribution to the university that they are naming one of the new buildings after him.
A genuine B minimum C modest D generous
name after 以…的名字來命名。genuine adj. 真正的，貨真價實的； genuine leather 真皮；
minimum adj. 最低的，最小的； modest adj. 謙虛謹慎的，適度的；
generous adj. 慷慨的，慷慨大方的（修飾貢獻等用這個）。
59. Helen was much kinder to her youngest child than she was to the others, _D_, of course, made the others jealous.
A who B that C what D which
which在這里是引導(dǎo)非限定性定語從句，which引導(dǎo)非限定性定語從句有2個特點：
1. which前面有逗號與其他句子分開。 2. which指的是前面整句話的內(nèi)容。
as也可以引導(dǎo)非限定性定語從句，指的都是一句話的內(nèi)容。
which指一句話的內(nèi)容只能置于該句之后，而as既可以在后也可以在前。
67. _C_ is known to the world, Mark Twain is great American writer.
A That B Which C As D It
60. In the advanced course students must take performance tests at monthly _B_.
A gaps B intervals C length D distance
interval n. 間隔（即可指空間間隔，也可指時間間隔），四級考試中?？紩r間間隔的概念。
interval是固定與介詞at搭配的。
23. Students or teachers can participate in excursions to lovely beaches around the island at regular _D_.
A gaps B rate C length D intervals
at regular rate 以規(guī)則的速度； at regular interval 以規(guī)則的時間間隔；
61. Mr. Johnson preferred _A_ heavier work to do.
A to be given B to be giving C to have given D having given
64. Our company decided to _D_ the contract because a number of the conditions in it had not been met.
A destroy B resist C assume D cancel
65. She is _C_ a musician than her brother.
A much of B much as C more of D more as
be of 具有某種性質(zhì)、品質(zhì)或特點；
66. Having been found guilty, the man was given a severe _B_ by the judge.
A service B sentence C crime D crisis
sentence n. 判決，判刑； crisis n. 危機； economic crisis 經(jīng)濟危機；
68. The residents, _C_ had been damaged by the flood, were given help by the Red Cross.
A all their homes B all whose homes C all of whose homes D all of their homes
當(dāng)給出了句子的主語，且后面有兩部分謂語動詞，這兩部分謂語動詞之間又沒有連接詞，
時態(tài)也不同時，離主語近的謂語動詞應(yīng)為從句的組合成分。
69. You can't afford to let the situation get worse. You must take _D_ to put it right.
A decisions B directions C sides D steps
take steps 采取措施，采取行動； take measures 采取措施；
70. Look at the terrible situation I am in! If only I _B_ your advice.
A follow B had followed C would follow D have followed
if only 如果，要是...就好了，其后面的句子一定要用虛擬語氣。
1. 如果if only后面的句子表示與現(xiàn)在或?qū)淼氖聦嵪喾矗@時謂語動詞用一般過去時體現(xiàn)虛擬語氣。
2. 如果if only后面的句子表示與過去的事實相反，這時謂語動詞用過去完成時體現(xiàn)虛擬語氣。
47. If only the committee _D_ the regulations and put them into effect as soon as possible
A approve B will approve C can approve D would approve
如果if only后面的句子表示與現(xiàn)在或?qū)淼氖聦嵪喾?，這時謂語動詞用一般過去時，
也可以用would + 動詞原形。
A in B at C for D on
52. There's little chance that mankind would _D_ a nuclear war.
A retain B endure C maintain D survive
retain vt. 保持，保留； endure v. 忍受； maintain vt. 維持，保持，堅持認為；
survive vi. 生存； vt. 活過 … （賓語為某種災(zāi)難）。 survive a flood 活過一場洪水。
前綴sur表示過 … ，外，超； vive 表示生活，強調(diào)活著。
54. They usually have less money at the end of the month than _C_ at the beginning.
A which is B which was C they have D it is
less … than句子前后要平衡結(jié)構(gòu)。
55. In the course of a day students do far more than just _A_ classes.
A attend B attended C to attend D attending
far more than 遠遠多于，遠不止于；也要句子前后平衡結(jié)構(gòu)。
56. The French pianist [n. 鋼琴師] who had been praised very highly _C_ to be a great disappointment.
A turned up B turned in C turned out D turned down
turn up 后面不加賓語表示出現(xiàn)，后面加賓語表示將聲音調(diào)高，調(diào)大；
turn in + 賓語 上繳，交出； turn down 將聲音調(diào)低，調(diào)?。痪芙^；
refuse sb. 指直接的回絕； turn sb. down 則指委婉的拒絕；
turn out + 動詞不定式 最終證明是，結(jié)果是。
57. Many difficulties have _B_ as a result of the change over to a new type of fuel.
A risen B arisen C raised D arrived
因本句未加賓語，估不應(yīng)選不及物動詞，可排除C項； arrive vi. 到達，抵達；
rise vi. 升起，升高（側(cè)重指旗幟或太陽升起）；數(shù)量的增高（側(cè)重指水位、價位）；
the sun rises in the east and sets in the west 太陽東升西落。
arise vi. 升起，升高，出現(xiàn)，發(fā)生（經(jīng)常與抽象名詞聯(lián)用）。
69. A completely new situation will _B_ when the examination system comes into existence.
A arise B rise C raise D arouse
33. Last year the advertising rate _D_ by 20 percent.
A raised B aroused C arose D rose
58. He made such a _D_ contribution to the university that they are naming one of the new buildings after him.
A genuine B minimum C modest D generous
name after 以…的名字來命名。genuine adj. 真正的，貨真價實的； genuine leather 真皮；
minimum adj. 最低的，最小的； modest adj. 謙虛謹慎的，適度的；
generous adj. 慷慨的，慷慨大方的（修飾貢獻等用這個）。
59. Helen was much kinder to her youngest child than she was to the others, _D_, of course, made the others jealous.
A who B that C what D which
which在這里是引導(dǎo)非限定性定語從句，which引導(dǎo)非限定性定語從句有2個特點：
1. which前面有逗號與其他句子分開。 2. which指的是前面整句話的內(nèi)容。
as也可以引導(dǎo)非限定性定語從句，指的都是一句話的內(nèi)容。
which指一句話的內(nèi)容只能置于該句之后，而as既可以在后也可以在前。
67. _C_ is known to the world, Mark Twain is great American writer.
A That B Which C As D It
60. In the advanced course students must take performance tests at monthly _B_.
A gaps B intervals C length D distance
interval n. 間隔（即可指空間間隔，也可指時間間隔），四級考試中?？紩r間間隔的概念。
interval是固定與介詞at搭配的。
23. Students or teachers can participate in excursions to lovely beaches around the island at regular _D_.
A gaps B rate C length D intervals
at regular rate 以規(guī)則的速度； at regular interval 以規(guī)則的時間間隔；
61. Mr. Johnson preferred _A_ heavier work to do.
A to be given B to be giving C to have given D having given
64. Our company decided to _D_ the contract because a number of the conditions in it had not been met.
A destroy B resist C assume D cancel
65. She is _C_ a musician than her brother.
A much of B much as C more of D more as
be of 具有某種性質(zhì)、品質(zhì)或特點；
66. Having been found guilty, the man was given a severe _B_ by the judge.
A service B sentence C crime D crisis
sentence n. 判決，判刑； crisis n. 危機； economic crisis 經(jīng)濟危機；
68. The residents, _C_ had been damaged by the flood, were given help by the Red Cross.
A all their homes B all whose homes C all of whose homes D all of their homes
當(dāng)給出了句子的主語，且后面有兩部分謂語動詞，這兩部分謂語動詞之間又沒有連接詞，
時態(tài)也不同時，離主語近的謂語動詞應(yīng)為從句的組合成分。
69. You can't afford to let the situation get worse. You must take _D_ to put it right.
A decisions B directions C sides D steps
take steps 采取措施，采取行動； take measures 采取措施；
70. Look at the terrible situation I am in! If only I _B_ your advice.
A follow B had followed C would follow D have followed
if only 如果，要是...就好了，其后面的句子一定要用虛擬語氣。
1. 如果if only后面的句子表示與現(xiàn)在或?qū)淼氖聦嵪喾矗@時謂語動詞用一般過去時體現(xiàn)虛擬語氣。
2. 如果if only后面的句子表示與過去的事實相反，這時謂語動詞用過去完成時體現(xiàn)虛擬語氣。
47. If only the committee _D_ the regulations and put them into effect as soon as possible
A approve B will approve C can approve D would approve
如果if only后面的句子表示與現(xiàn)在或?qū)淼氖聦嵪喾?，這時謂語動詞用一般過去時，
也可以用would + 動詞原形。