有关连接词的语法填空(参考资料)
(1)
Influenza, or flu, is a common infection of the nose and throat, and sometimes the lungs. The cause is a virus [1] _______ passes from one person to another. The virus spreads through the air [2]______ an infected person expels air suddenly.
Medical experts have identified three major kinds of influenza. They call them type A, B and C. Type C is the least serious. People may not even know they have it. [3] ______ researchers study the other two kinds very closely. Viruses change to survive. This can make it difficult for the body to recognize [4]_______ fight an infection.
A person [5] _____has suffered one kind of flu cannot develop that same kind again. The body’s defense system produces antibodies（抗体）. These substances stay in the blood and destroy the virus [6] ______ it appears again. [7] ______the body may not recognize a flu virus [8] ________ has even a small change.
Each year, researchers develop vaccines（疫苗）to prevent the spread of the flu virus. The World Health Organization holds meetings in [9] ______ experts discuss [10]______ kinds of flu viruses to include in the next vaccine.
keys
1. that/which。引导定语从句并在从句中作主语。
2. when。引导状语从句。“当感染者突然呼气时，病毒就传播到空气中。”
3. But。转折关系。C型流行性感冒不为人所觉察，但研究人员认真研究另外两种。
4. and。“识别并与感染作斗争”，并列关系。
5. who。引导定语从句并在从句中作主语。
6. if/when。引导状语从句。
7. But。抗体能破坏病毒，但当病毒有细微改变时身体却无法识别它，转折关系。
8. that/which。引导定语从句并在从句中作主语。
9. which。引导定语从句。in which指代in the meeting。
10. what。引导宾语从句。专家讨论下一代疫苗将包含哪些流感病毒。
(2)
American scientists have discovered that walnut trees can produce more than walnuts. The scientists say walnut trees also can make a chemical form of the popular pain-killing medicine aspirin. The trees do this under the stress of disease [1] ____other threats. Scientists say the chemical may help the trees reduce damage from dry weather, unseasonable temperatures [2]____ other changes in the environment.
The results are important [3]_________ presence of the chemical could warn growers early [4]______ a tree is in danger. Growers could recognize a problem [5]_____ leaves on walnut trees die and fall off. The scientists said the findings also show [6]_____ a plant can communicate with other plants through the atmosphere. For example, a tree could communicate [7] _______ it is under attack from insects. With that information, a grower could begin corrective treatment.
Researchers have known for a long time [8]_______ laboratory plants may produce methyl salicylate, aspirin’s chemical form. Aspirin was first produced from the bark covering on willow trees. [9]______the researchers had never before found methyl salicylate in a forest. They had not confirmed that trees could emit, [10] _____ give out, large amounts of the chemical into the atmosphere.
keys
1. or。“疾病的压力或者其它威胁”是选择关系，故用or。
2. and。并列关系，用and.
3. because。因果关系。译文：“这项研究结果重要，因为这种化学物质的存在能够向种植者发出树木有危险的警告”。
4. that。引导宾语从句。warn sb. that ... ，向某人警告某事。
5. before。树叶死亡或落下之前就发出警告。
6. that。引导宾语从句。
7. when。引导时间状语从句。当树木受到昆虫攻击时，能与其它树木进行信息交流。
8. that。引导宾语从句，从句及物动词grow的宾语。
9. But。转折关系。此句译为：“阿斯匹林最初产于柳树皮，但之前研究人员没有在森林中发现水杨酸甲酯。”
10. or。逗号后用or可以表示解释，“或者说”。
(3)
My mother insisted [1] ______ everyone in her life treat her with respect. [2] _______ she wasn’t wealthy [3]____ well educated, my mother not only understood and appreciated her value,
[4]________ believed in it strongly.
[5]______ she learned my father was cheating on her, she insisted [6]______ he move out of our home. Not the next day or the next week... To me, as a child, [7]_______ she refused to take my father back seemed harsh, even cruel.
As a woman, however, I have come to understand it. For my mother, putting Daddy out of the house [8]______ her life wasn’t about pride; it was about principle, the one she had always lived by, the one[9] __________she believed in with all her heart: No one was going to love and respect you [10]______ you loved and respected yourself.
keys
1. that
2. Though
3. or
4. but (also)
5. When
6. that
7. that
8. and
9. that /who/whom 10. unless