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[填空(1)] 西瓜属异花授粉作物，由蜜蜂，蓟马、蚂蚁等传粉，容易因自然杂交而发生混杂退化。因此，西瓜制种要求隔离， 授粉，周边 无同种作物种植。[填空(2)] 目前，黄瓜杂交制种隔离方式有 露地制种和 制种两种。 [填空(3)] 苦瓜杂交制种有 制种和 杂交制种两种方法。[填空(4)] 西瓜去取雄授粉前对父母本植株进行严格检查，发现 株、 株及时拔除。[填空(5)] 西瓜去雄时选花标准为： 膨大， 黄绿色，花瓣边缘鲜黄色。[填空(6)] 黄瓜品种间隔离 米。[填空(7)] 黄瓜制种采摘时没有 或 不清的果实不采摘，瓜型和颜色不一样的清除。[填空(8)] 甜瓜杂种一代有明显的 ，增产幅度20～90%，在含糖量、耐贮性等方面都有提高。[填空(9)] 西是雌雄 异花作物。[填空(10)] 南瓜杂交制种也采取露地水旱塘地膜覆盖栽培方式，父、母本 相遇和父本 供应是南瓜制种成败的关键。
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【单选题】It is not very healthy t o jog beside a motorway because of the .
A.
many accidents
B.
bicycles
C.
Air pollution
D.
other people
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【单选题】The main disadvantage of the automation system is()
A.
it increases pilot workload
B.
it makes more errors
C.
when manual operation is necessary, take over operation becomes difficult
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【单选题】标题字号大小一般选择( )像素。
A.
12
B.
14
C.
18
D.
22
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【单选题】According to the passage, the main disadvantage with reconfiguring diet to lessen water usage is
A.
most North Americans would be unlikely to shift their diets simply in order to accommodate the exigencies of water conservation
B.
the gains provided by diets with less water-intensive production would likely be less useful in areas with greater aquifer resources
C.
people in Asia and certain European countries are dependent on meat-products and could not do without them
D.
diets with less water-intensive production tend to be less healthy than those with more water-intense production
E.
governments of certain countries would be unlikely to promote programs for diet change given their possible negative effect on those countries' economies
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【单选题】Bypass operation has become very popular in the United States because ______.
A.
it is one of the most common major operations
B.
it is more effective than any other medicine
C.
the standard of living in America is much higher than that in any other country
D.
it can bring more money to the hospitals and doctors
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【简答题】The chair looks rather unusual in shape, but it is very comfortable to sit ______. A) by              B) on          C) with         D) at
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【单选题】This is not an economical way to get more water; _________,it is very expensive.
A.
on the contrary
B.
on the other hand
C.
in a word
D.
rather than
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【单选题】According to the passage, the main disadvantage of person-on-the-street interviews is that they
A.
are not based on a representative sampling
B.
are used only on television
C.
are not carefully worded
D.
reflect political opinions
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【单选题】A) It has a solid plastic frame. B) It consists of an inner and an outer tent. prefix="o" ns="urn:schemas-microsoft-com:office:office" ?xml:namespace> C) It is very convenient to set up. D) It is sold...
A.
It has a solid plastic frame.
B.
It consists of an inner and an outer tent.
C.
It is very convenient to set up.
D.
It is sold to many Continental countries.
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相关题目：
【单选题】It is not very healthy t o jog beside a motorway because of the .
A.
many accidents
B.
bicycles
C.
Air pollution
D.
other people
查看完整题目与答案
【简答题】Slang is a popular, less official and often very current form of language. It is an important part of a living language and is constantly changing as language changes. Slang is often playful, direct a...
查看完整题目与答案
【单选题】The main disadvantage of the automation system is()
A.
it increases pilot workload
B.
it makes more errors
C.
when manual operation is necessary, take over operation becomes difficult
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【单选题】标题字号大小一般选择( )像素。
A.
12
B.
14
C.
18
D.
22
查看完整题目与答案
【单选题】According to the passage, the main disadvantage with reconfiguring diet to lessen water usage is
A.
most North Americans would be unlikely to shift their diets simply in order to accommodate the exigencies of water conservation
B.
the gains provided by diets with less water-intensive production would likely be less useful in areas with greater aquifer resources
C.
people in Asia and certain European countries are dependent on meat-products and could not do without them
D.
diets with less water-intensive production tend to be less healthy than those with more water-intense production
E.
governments of certain countries would be unlikely to promote programs for diet change given their possible negative effect on those countries' economies
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【单选题】Bypass operation has become very popular in the United States because ______.
A.
it is one of the most common major operations
B.
it is more effective than any other medicine
C.
the standard of living in America is much higher than that in any other country
D.
it can bring more money to the hospitals and doctors
查看完整题目与答案
【简答题】The chair looks rather unusual in shape, but it is very comfortable to sit ______. A) by              B) on          C) with         D) at
查看完整题目与答案
【单选题】This is not an economical way to get more water; _________,it is very expensive.
A.
on the contrary
B.
on the other hand
C.
in a word
D.
rather than
查看完整题目与答案
【单选题】According to the passage, the main disadvantage of person-on-the-street interviews is that they
A.
are not based on a representative sampling
B.
are used only on television
C.
are not carefully worded
D.
reflect political opinions
查看完整题目与答案
【单选题】A) It has a solid plastic frame. B) It consists of an inner and an outer tent. prefix="o" ns="urn:schemas-microsoft-com:office:office" ?xml:namespace> C) It is very convenient to set up. D) It is sold...
A.
It has a solid plastic frame.
B.
It consists of an inner and an outer tent.
C.
It is very convenient to set up.
D.
It is sold to many Continental countries.
查看完整题目与答案
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