alcohol extraction and water precipitation

请阅读短文，完成此题。
When we analyze the salt salinity(盐溶度 ) of ocean waters, we find that it varies only slightly from place to place. Nevertheless, some of these small changes are important. There are three basic processes that cause a change in oceanic salinity. One of these is the subtraction of water from the ocean by means of evaporation. In this manner, the salinity is increased, since the salt stays behind. If this is carried to the extreme, of course, white salt would be left behind; this, by the way, is how much of the table salt we use is actually obtained.
The opposite of evaporation is precipitation, such as rain, by which water is added to the ocean. Here the ocean is being diluted so that the salinity is decreased. This may occur in areas of
high rainfall or in coastal regions where rivers flow into the ocean. Thus salinity may be increased by the subtraction of water by-evaporation, or decreased by the addition of fresh water by precipitation.
Normally, in hot regions where the sun is very strong, the ocean salinity is somewhat higher than it is in other parts of the world where there is not as much evaporation. Similarly, in coastal regions where rivers dilute the sea, salinity is somewhat lower than in other oceanic areas.
A third process by which salinity may be altered is associated with the formation and melting of sea ice. When seawater is frozen, the dissolved materials are left behind. In this manner, seawater directly beneath freshly formed sea ice has a higher salinity than it did before the ice appeared. Of course, when this ice melts, it will tend to decrease the salinity of the surrounding water.
In the Weddell Sea, the densest water in the ocean is formed as a result of this freezing process, which increases the salinity of cold water. This heavy water sinks and is found in the deeper portion of the oceans of the world.

Which of the following is not the cause of the decrease in the oceanic salinity?
查看材料

A．Precipitation.
B．Rain and snow.
C．Formation of ice.
D．Addition of water by rivers.

请阅读短文，完成此题。
When we analyze the salt salinity(盐溶度 ) of ocean waters, we find that it varies only slightly from place to place. Nevertheless, some of these small changes are important. There are three basic processes that cause a change in oceanic salinity. One of these is the subtraction of water from the ocean by means of evaporation. In this manner, the salinity is increased, since the salt stays behind. If this is carried to the extreme, of course, white salt would be left behind; this, by the way, is how much of the table salt we use is actually obtained.
The opposite of evaporation is precipitation, such as rain, by which water is added to the ocean. Here the ocean is being diluted so that the salinity is decreased. This may occur in areas of
high rainfall or in coastal regions where rivers flow into the ocean. Thus salinity may be increased by the subtraction of water by-evaporation, or decreased by the addition of fresh water by precipitation.
Normally, in hot regions where the sun is very strong, the ocean salinity is somewhat higher than it is in other parts of the world where there is not as much evaporation. Similarly, in coastal regions where rivers dilute the sea, salinity is somewhat lower than in other oceanic areas.
A third process by which salinity may be altered is associated with the formation and melting of sea ice. When seawater is frozen, the dissolved materials are left behind. In this manner, seawater directly beneath freshly formed sea ice has a higher salinity than it did before the ice appeared. Of course, when this ice melts, it will tend to decrease the salinity of the surrounding water.
In the Weddell Sea, the densest water in the ocean is formed as a result of this freezing process, which increases the salinity of cold water. This heavy water sinks and is found in the deeper portion of the oceans of the world.

Which of the following statements is TRUE according to the passage?
查看材料

A．Oceanic salinity has great effect on sea life.
B．Many factors combine to cause changes in oceanic salinity.
C．The movement of the water is related to the amount of salt.
D．The temperature of the water has much to do with the oceanic salinity.

共用题干
The Drink Your Body Needs Most

I Our bodies are estimated to be about 60% to 70% water. Blood is mostly water,and
our muscles,lungs,and brain all contain a lot of water. Water is needed to regulate body
temperature and to provide the means for nutrients（滋养物）to travel to all our organs.
Water also transports oxygen to our cells,removes waste,and protects our joints and
organs.
2 We lose water through urination（排尿）,respiration（呼吸）,and by sweating. If you
are very active,you lose more water than if you do not take much exercise.Symptoms of
mild dehydration（脱水）include chronic pains in joints and muscles, lower back pain,
headaches, and constipation（便秘）.A strong smell to your urine, along with a yellow
color indicates that you are not getting enough water. Thirst is an obvious sign of
dehydration and in fact,you need water long before you feel thirsty.
3 A good rule of thumb（好的做法）is to take your bod犷weight in pounds and divide that
number in half. That gives you the number of ounces（盎司）of water per day that you
need.For example,if you weigh 160 pounds,you should drink at least 80 ounces of water
per day.If you exercise you should drink another 8-ounce glass of water for every 20
minutes you are active.If you drink coffee or alcohol,you should add at least an equal
amount of water. When you are traveling on an airplane,it is good to have 8 ounces of
water for every hour you are on board the plane.
4 It may be difficult to drink enough water on a busy day.Be sure you have water handy at
all times by keeping a bottle for water with you when you are working,traveling,or
exercising.If you get bored with plain water,add a bit of lemon for a touch of flavor.There
are some brands of flavored water available,but some of them have sugar or artificial
sweeteners that you don't need.

The amount of water your body needs per day is closely related________.
A:in your body
B:without water
C:before long
D:for a change
E:on a busy day
F:to your weight

共用题干
The Drink Your Body Needs Most

I Our bodies are estimated to be about 60% to 70% water. Blood is mostly water,and
our muscles,lungs,and brain all contain a lot of water. Water is needed to regulate body
temperature and to provide the means for nutrients（滋养物）to travel to all our organs.
Water also transports oxygen to our cells,removes waste,and protects our joints and
organs.
2 We lose water through urination（排尿）,respiration（呼吸）,and by sweating. If you
are very active,you lose more water than if you do not take much exercise.Symptoms of
mild dehydration（脱水）include chronic pains in joints and muscles, lower back pain,
headaches, and constipation（便秘）.A strong smell to your urine, along with a yellow
color indicates that you are not getting enough water. Thirst is an obvious sign of
dehydration and in fact,you need water long before you feel thirsty.
3 A good rule of thumb（好的做法）is to take your bod犷weight in pounds and divide that
number in half. That gives you the number of ounces（盎司）of water per day that you
need.For example,if you weigh 160 pounds,you should drink at least 80 ounces of water
per day.If you exercise you should drink another 8-ounce glass of water for every 20
minutes you are active.If you drink coffee or alcohol,you should add at least an equal
amount of water. When you are traveling on an airplane,it is good to have 8 ounces of
water for every hour you are on board the plane.
4 It may be difficult to drink enough water on a busy day.Be sure you have water handy at
all times by keeping a bottle for water with you when you are working,traveling,or
exercising.If you get bored with plain water,add a bit of lemon for a touch of flavor.There
are some brands of flavored water available,but some of them have sugar or artificial
sweeteners that you don't need.

Dehydration may occur if there is a shortage of water_________.
A:in your body
B:without water
C:before long
D:for a change
E:on a busy day
F:to your weight

共用题干
The Drink Your Body Needs Most
1. Our bodies are estimated to be about 60%to 70%water. Blood is mostly water, and our mus- dles,lungs and brain all contain a lot of water. Water is needed to regulate body temperature and to provide the means for nutrients（滋养物）to travel to all our organs. Water also transports oxy-gen to our cells,removes waste,and protects our joints and organs.
2. We lose water through urination（排尿）, respiration（呼吸）, and by sweating. If you are very active,you lose more water than if you do not take much exercise.Symptoms of mild dehydration （脱水）include chronic pains in joints and muscles,lower back pain,headaches,and constipation
（便秘）.A strong smell to your urine,along with a yellow color indicates that you are not getting enough water. Thirst is an obvious sign of dehydration and in fact,you need water long before you feel thirsty.
3 .A good rule of thumb（好的做法）is to take your body weight in pounds and divide that num- her in half. That gives you the number of ounces（盎司）of water per day that you need.For ex-ample,if you weigh 160 pounds,you should drink at least 80 ounces of water per day.If you ex- ercise you should drink another 8-ounce glass of water for every 20 minutes you are active.If you drink coffee or alcohol,you should add at least an equal amount of water. When you are traveling on an airplane,it is good to have 8 ounces of water for every hour you are on board the plane.
4 .It may be difficult to drink enough water on a busy day.Be sure you have water handy at all times by keeping a bottle for water with you when you are working,traveling,or exercising. If you get bored with plain water,add a bit of lemon for a touch of flavor. There are some brands of fla-vored water available,but some of them have sugar or artificial sweeteners that you don't need.

The amount of water your body needs per day is related_________.
A: in your body
B: without water
C: before long
D: for a change
E: on a busy day
F: to your weight

共用题干
The Drink Your Body Needs Most
1. Our bodies are estimated to be about 60%to 70%water. Blood is mostly water, and our mus- dles,lungs and brain all contain a lot of water. Water is needed to regulate body temperature and to provide the means for nutrients（滋养物）to travel to all our organs. Water also transports oxy-gen to our cells,removes waste,and protects our joints and organs.
2. We lose water through urination（排尿）, respiration（呼吸）, and by sweating. If you are very active,you lose more water than if you do not take much exercise.Symptoms of mild dehydration （脱水）include chronic pains in joints and muscles,lower back pain,headaches,and constipation
（便秘）.A strong smell to your urine,along with a yellow color indicates that you are not getting enough water. Thirst is an obvious sign of dehydration and in fact,you need water long before you feel thirsty.
3 .A good rule of thumb（好的做法）is to take your body weight in pounds and divide that num- her in half. That gives you the number of ounces（盎司）of water per day that you need.For ex-ample,if you weigh 160 pounds,you should drink at least 80 ounces of water per day.If you ex- ercise you should drink another 8-ounce glass of water for every 20 minutes you are active.If you drink coffee or alcohol,you should add at least an equal amount of water. When you are traveling on an airplane,it is good to have 8 ounces of water for every hour you are on board the plane.
4 .It may be difficult to drink enough water on a busy day.Be sure you have water handy at all times by keeping a bottle for water with you when you are working,traveling,or exercising. If you get bored with plain water,add a bit of lemon for a touch of flavor. There are some brands of fla-vored water available,but some of them have sugar or artificial sweeteners that you don't need.

Paragraph 1________
A: Ounces of water needed per day
B:.Importance of water
C: Composition of water
D: Signs of dehydration
E: Supply of water
F: Necessity for bringing a bottle for water

请阅读短文，完成此题。
When we analyze the salt salinity(盐溶度 ) of ocean waters, we find that it varies only slightly from place to place. Nevertheless, some of these small changes are important. There are three basic processes that cause a change in oceanic salinity. One of these is the subtraction of water from the ocean by means of evaporation. In this manner, the salinity is increased, since the salt stays behind. If this is carried to the extreme, of course, white salt would be left behind; this, by the way, is how much of the table salt we use is actually obtained.
The opposite of evaporation is precipitation, such as rain, by which water is added to the ocean. Here the ocean is being diluted so that the salinity is decreased. This may occur in areas of
high rainfall or in coastal regions where rivers flow into the ocean. Thus salinity may be increased by the subtraction of water by-evaporation, or decreased by the addition of fresh water by precipitation.
Normally, in hot regions where the sun is very strong, the ocean salinity is somewhat higher than it is in other parts of the world where there is not as much evaporation. Similarly, in coastal regions where rivers dilute the sea, salinity is somewhat lower than in other oceanic areas.
A third process by which salinity may be altered is associated with the formation and melting of sea ice. When seawater is frozen, the dissolved materials are left behind. In this manner, seawater directly beneath freshly formed sea ice has a higher salinity than it did before the ice appeared. Of course, when this ice melts, it will tend to decrease the salinity of the surrounding water.
In the Weddell Sea, the densest water in the ocean is formed as a result of this freezing process, which increases the salinity of cold water. This heavy water sinks and is found in the deeper portion of the oceans of the world.

It can be known from the passage that increase in the salinity of ocean water is caused by__________.
查看材料

A．melting of sea ice
B．precipitation
C．evaporation
D．supplement of salt

请阅读短文，完成此题。
When we analyze the salt salinity(盐溶度 ) of ocean waters, we find that it varies only slightly from place to place. Nevertheless, some of these small changes are important. There are three basic processes that cause a change in oceanic salinity. One of these is the subtraction of water from the ocean by means of evaporation. In this manner, the salinity is increased, since the salt stays behind. If this is carried to the extreme, of course, white salt would be left behind; this, by the way, is how much of the table salt we use is actually obtained.
The opposite of evaporation is precipitation, such as rain, by which water is added to the ocean. Here the ocean is being diluted so that the salinity is decreased. This may occur in areas of
high rainfall or in coastal regions where rivers flow into the ocean. Thus salinity may be increased by the subtraction of water by-evaporation, or decreased by the addition of fresh water by precipitation.
Normally, in hot regions where the sun is very strong, the ocean salinity is somewhat higher than it is in other parts of the world where there is not as much evaporation. Similarly, in coastal regions where rivers dilute the sea, salinity is somewhat lower than in other oceanic areas.
A third process by which salinity may be altered is associated with the formation and melting of sea ice. When seawater is frozen, the dissolved materials are left behind. In this manner, seawater directly beneath freshly formed sea ice has a higher salinity than it did before the ice appeared. Of course, when this ice melts, it will tend to decrease the salinity of the surrounding water.
In the Weddell Sea, the densest water in the ocean is formed as a result of this freezing process, which increases the salinity of cold water. This heavy water sinks and is found in the deeper portion of the oceans of the world.

This passage mainly tells us about__________.
查看材料

A．the analysis of the salinity of ocean waters
B．the causes of the variation in oceanic salinity
C．the importance of the changes in oceanic salinity
D．the different forms of salts in ocean waters

共用题干
The Drink Your Body Needs Most

I Our bodies are estimated to be about 60% to 70% water. Blood is mostly water,and
our muscles,lungs,and brain all contain a lot of water. Water is needed to regulate body
temperature and to provide the means for nutrients（滋养物）to travel to all our organs.
Water also transports oxygen to our cells,removes waste,and protects our joints and
organs.
2 We lose water through urination（排尿）,respiration（呼吸）,and by sweating. If you
are very active,you lose more water than if you do not take much exercise.Symptoms of
mild dehydration（脱水）include chronic pains in joints and muscles, lower back pain,
headaches, and constipation（便秘）.A strong smell to your urine, along with a yellow
color indicates that you are not getting enough water. Thirst is an obvious sign of
dehydration and in fact,you need water long before you feel thirsty.
3 A good rule of thumb（好的做法）is to take your bod犷weight in pounds and divide that
number in half. That gives you the number of ounces（盎司）of water per day that you
need.For example,if you weigh 160 pounds,you should drink at least 80 ounces of water
per day.If you exercise you should drink another 8-ounce glass of water for every 20
minutes you are active.If you drink coffee or alcohol,you should add at least an equal
amount of water. When you are traveling on an airplane,it is good to have 8 ounces of
water for every hour you are on board the plane.
4 It may be difficult to drink enough water on a busy day.Be sure you have water handy at
all times by keeping a bottle for water with you when you are working,traveling,or
exercising.If you get bored with plain water,add a bit of lemon for a touch of flavor.There
are some brands of flavored water available,but some of them have sugar or artificial
sweeteners that you don't need.

Paragraph 4__________
A:Ounces of water needed per day
B:Importance of water
C:Composition of water
D:Signs of dehydration
E:Supply of water
F:Necessity for bringing a bottle for water with you

共用题干
The Drink Your Body Needs Most

I Our bodies are estimated to be about 60% to 70% water. Blood is mostly water,and
our muscles,lungs,and brain all contain a lot of water. Water is needed to regulate body
temperature and to provide the means for nutrients（滋养物）to travel to all our organs.
Water also transports oxygen to our cells,removes waste,and protects our joints and
organs.
2 We lose water through urination（排尿）,respiration（呼吸）,and by sweating. If you
are very active,you lose more water than if you do not take much exercise.Symptoms of
mild dehydration（脱水）include chronic pains in joints and muscles, lower back pain,
headaches, and constipation（便秘）.A strong smell to your urine, along with a yellow
color indicates that you are not getting enough water. Thirst is an obvious sign of
dehydration and in fact,you need water long before you feel thirsty.
3 A good rule of thumb（好的做法）is to take your bod犷weight in pounds and divide that
number in half. That gives you the number of ounces（盎司）of water per day that you
need.For example,if you weigh 160 pounds,you should drink at least 80 ounces of water
per day.If you exercise you should drink another 8-ounce glass of water for every 20
minutes you are active.If you drink coffee or alcohol,you should add at least an equal
amount of water. When you are traveling on an airplane,it is good to have 8 ounces of
water for every hour you are on board the plane.
4 It may be difficult to drink enough water on a busy day.Be sure you have water handy at
all times by keeping a bottle for water with you when you are working,traveling,or
exercising.If you get bored with plain water,add a bit of lemon for a touch of flavor.There
are some brands of flavored water available,but some of them have sugar or artificial
sweeteners that you don't need.

One cannot live________
A:in your body
B:without water
C:before long
D:for a change
E:on a busy day
F:to your weight

共用题干
The Drink Your Body Needs Most

1 Our bodies are estimated to be about 60% to 70% water.Blood is mostly water,and
our muscles,lungs,and brain all contain a lot of water.Water is needed to regulate body
temperature and to provide the means for nutrients（滋养物）to travel to all our organs.
Water also transports oxygen to our cells,removes waste,and protects our joints and
organs.
2 We lose water through urination（排尿）,respiration（呼吸）,and by sweating. If you
are very active,you lose more water than if you do not take much exercise.Symptoms of
mild dehydration（脱水）include chronic pains in joints and muscles , lower back pain,
headaches, and constipation（便秘）.A strong smell to your urine , along with a yellow
color indicates that you are not getting enough water.Thirst is an obvious sign of
dehydration and in fact,you need water long before you feel thirsty.
3 A good rule of thumb（好的做法）is to take your body weight in pounds and divide that
number in half. That gives you the number of ounces（盎司）of water per day that you
need.For example,if you weigh 160 pounds,you should drink at least 80 ounces of water
per day.If you exercise you should drink another 8-ounce glass of water for every 20 minutes you are active.If you drink coffee or alcohol,you should add at least an equal
amount of water.When you are traveling on an airpiane,it is good to have 8 ounces of
water for every hour you are on board the plane.
4 It may be difficult to drink enough water on a busy day.Be sure you have water handy at
all times by keeping a bottle for water with you when you are working,traveling,or
exercising.If you get bored with plain water,add a bit of lemon for a touch of flavor.There
are some brands of flavored water available,but some of them have sugar or artificial
sweeteners that you don't need.

One cannot live_______.
A:in your body
B:without water
C:before long
D:for a change
E:on a busy day
F:to your weight