[不定项选择题]共用题干 Where Has the Salt Come from?

Every now and then,we meet a fact about our earth that makes us feel strange and no
answer for the fact has yet been found.Such a fact is the existence of salt in the oceans.
How did it get there?
We simply do not know how the salt got into the ocean!We do know,of course,that
salt is water-soluble,and so passes into the oceans with rainwater.The salt of the earth's
surface is constantly being dissolved（溶解）and is passing into the ocean.
But we do not know whether this can explain the huge quantity of salt in oceans.If all
the oceans were dried up,enough salt would be left to build a wall 180 miles high and a
mile thick. Such a wall would reach once around the world at the Equator（赤道）!
The common salt that we all use is produced from seawater or the water of salt lakes,
from salt springs（源泉）and from deposits of rock salt. The concentration（浓度）of salt in
seawater ranges from about three percent to three-and-one-half percent. The Dead Sea,
which covers an area of about 340 square miles,contains about 11,600,000,000 tons of
salt!
On the average, a gallon（加仑）of seawater contains about a quarter of a pound of
salt.The beds of rock salt that are found in various parts of the world were all originally
formed by the evaporation（蒸发）of seawater millions of years ago. It is believed that the
thick rock-salt deposits were formed after about nine-tenth of theY volume of seawater had
been evaporated.
Most commercial salt is obtained from rock salt.The usual method is to drill wells（井）
down to the salt beds. Pure water is pumped down（抽进去）through a pipe. The water
dissolves the salt and it is forced through another pipe up to the surface.
A.Right
B.Wrong
C.Not mentioned

[不定项选择题]共用题干 Where Has the Salt Come from?

Every now and then,we meet a fact about our earth that makes us feel strange and no
answer for the fact has yet been found.Such a fact is the existence of salt in the oceans.
How did it get there?
We simply do not know how the salt got into the ocean!We do know,of course,that
salt is water-soluble,and so passes into the oceans with rainwater.The salt of the earth's
surface is constantly being dissolved（溶解）and is passing into the ocean.
But we do not know whether this can explain the huge quantity of salt in oceans.If all
the oceans were dried up,enough salt would be left to build a wall 180 miles high and a
mile thick. Such a wall would reach once around the world at the Equator（赤道）!
The common salt that we all use is produced from seawater or the water of salt lakes,
from salt springs（源泉）and from deposits of rock salt. The concentration（浓度）of salt in
seawater ranges from about three percent to three-and-one-half percent. The Dead Sea,
which covers an area of about 340 square miles,contains about 11,600,000,000 tons of
salt!
On the average, a gallon（加仑）of seawater contains about a quarter of a pound of
salt.The beds of rock salt that are found in various parts of the world were all originally
formed by the evaporation（蒸发）of seawater millions of years ago. It is believed that the
thick rock-salt deposits were formed after about nine-tenth of theY volume of seawater had
been evaporated.
Most commercial salt is obtained from rock salt.The usual method is to drill wells（井）
down to the salt beds. Pure water is pumped down（抽进去）through a pipe. The water
dissolves the salt and it is forced through another pipe up to the surface.
A.Right
B.Wrong
C.Not mentioned

[不定项选择题]Where did the noise come from? __________
A.From the small house
B.From Mrs．Janes
C.From the tyres
D.From the engine

[不定项选择题]共用题干 Sauna
Ceremonial bathing has existed for.thousands of years and has many forms,one of which is the sauna.The Finns have perfected the steam bath,or sauna,which may be taken,usually in an enclosed room,by pouring water over hot rocks or as a dry heat bath.The Japanese,Greeks,Turks and Russians as well as Native Americans have forms of the sweat bath in their bathing rituals.Dry heat and steam baths had advocates in ancient Rome and pre-Columbian Americans used sweat lodges.
The earliest saunas were probably underground caves heated by a fire that naturally filled with smoke as chimney making was unknown at that time.A fire kept in a fire-pit would heat the rock walls of the cave.After reaching full heat,the smoke was let out of the cave and the stones would retain heat for several hours.A few people today say that the smoke sauna,"savusauna",is the only true sauna experience and that all saunas should have at least a background odor or smoke.Today most saunas use electric stoves,although gas and wood-burning stoves are available.
Saunas are relaxing and stress relieving.Those with muscle aches or arthritis may find that the heat relaxes muscles and relieves pain and inflammation.Asthma patients find that the heat enlarges air passageways of the lung and facilitates breathing.Saunas do not cure the common cold but they may help to alleviate congestion and speed recovery time.The body's core temperature usually rises 1-2 degrees while in the sauna,thus imitating a slight fever.The sauna could be considered to follow the old saying"feed a cold,starve aestarve a lever".The regular use of a sauna may decrease the likelihood of getting a cold in the first place.
Sauna is good for your skin as the blood flow to the skin increases and sweating occurs.Adults sweat about 2 lbs of water per hour on average in a sauna.A good sweat removes dirt and grime from pores and gives the skin a healthy glow.The loss in water weight is temporary as the body's physiological mechanisms will quickly restore proper volumes.The cardiovascular system gets a work out as the heart must pump harder and faster to move blood to the surface for heat exchange.Heart rate may increase from 72 beats per minute on average to 100-150 beats per minute.
A normal heart can handle these stresses but those with heart trouble wishing to begin to use a sauna should seek a doctor's advice.The elderly and those with diabetes should check with their doctor prior to beginning to take saunas.Pregnant women should not take saunas,particularly in the first three months.Indeed,everyone just starting out should take short sessions at first to become accustomed to this type of bath. Who are advised not to take a sauna?
A.Elderly people.
B.Pregnant women.
C.People with heart trouble.
D.All of the above.

[不定项选择题]共用题干 第二篇

Some People do Not Taste Salt Like Others

Low-salt foods may be harder for some people to like than others,according to a study by a Penn State
College of Agricultural Sciences food scientist.The research indicates that genetic factors influence some of
the difference in the levels of salt we like to eat.
Those conclusions are important because recent,well-publicized efforts to reduce the salt content in food
have left many people struggling to accept fare that simply does not taste as good to them as it does to others,
pointed out John Hayes,assistant professor of food science who was lead investigator on the study.
Diets high in salt can increase the risk of high blood pressure and stroke.That is why public health ex-
perts and food companies are working together on ways to help consumers lower salt intake through foods that
are enjoyable to eat.This study increases undersfanding of salt preference and consumption.
The research involved 87 carefully screened participants who sampled salty foods such as soup and
chips,on multiple occasions,spread out over weeks.Test subjects were 45 men and 42 women,reportedly
healthy,ranging in age from 20 to 40 years.The sample was composed of individuals who were not actively
modifying their dietary intake and did not smoke cigarettes.They rated the intensity of taste on a commonly
used scientific scale,ranging from barely detectable to strongest sensation of any kind.
"Most of us like the taste of salt.However,some individuals eat more salt,both because they like the
taste of saltiness more,and also because it is needed to block other unpleasant tastes in food,"said Hayes.
"Supertasters,people who experience tastes more intensely,consume more salt than nontasters do.Snack
foods have saltiness as their primary flavor,and at least for these foods,more is better,so the supertasters
seem to like them more."
However,supertasters also need higher levels of salt to block unpleasant bitter tastes in food such as
cheese,Hayes noted."For example,cheese is a wonderful blend of dairy flavors from fermented milk,but al-
so bitter tastes from ripening that are blocked by salt,"he said."A supertaster finds low-salt cheese unpleasant
because the bitterness is too pronounced."
Hayes cited research done more than 75 years ago by a chemist named Fox and a geneticist named
Blakeslee,showing that individuals differ in their ability to taste certain chemicals.As a result,Hayes ex-
plained,we know that a wide range in taste acuity exists,and this variation is as normal as variations in eye
and hair color.
"Some people,called supertasters,'describe bitter compounds as being extremely bitter,while others,
called nontasters,find these same bitter compounds to be tasteless or only weakly bitter,"he said."Response
to bitter compounds is one of many ways to identify biological differences in food preference because super-
tasting is not limited to bitterness." It can be inferred from the last paragraph that taste acuity is_______.
A.identified with certain chemicals
B.developed over time after birth
C.related to one's eye and hair color
D.genetically determined

[不定项选择题]共用题干 第三篇

Some People do Not Taste Salt Like Others

Low-salt foods may be harder for some people to like than others,according to a study by a Penn State
College of Agricultural Sciences food scientist. The research indicates that genetic factors influence some of
the difference in the levels of salt we like to eat.
Those conclusions are important because recent,well-publicized efforts to reduce the salt content in
food have left many people struggling to accept fare that simply does not taste as good to them as it does to
others,pointed out John Hayes,assistant professor of food science,who was lead investigator on the study.
Diets high in salt can increase the risk of high blood pressure and stroke.That is why public health ex-
perts and food companies are working together on ways to help consumers lower salt intake through foods that
are enjoyable to eat. This study increases understanding of salt preference and consumption.
The research involved 87 carefully screened participants who sampled salty foods such as soup and
chips,on multiple occasions,spread out over weeks.Test subjects were 45 men and 42 women,reportedly
healthy,ranging in age from 20 to 40 years.The sample was composed of individuals who were not actively
modifying their dietary intake and did not smoke cigarettes.They rated the intensity of taste on a commonly
used scientific scale,ranging from barely detectable to strongest sensation of any kind.
"Most of us like the taste of salt. However,some individuals eat more salt,both because they like the
taste of saltiness more,and also because it is needed to block other unpleasant tastes in food."said Hayes.
"Supertasters,people who experience tastes more intensely,consume more salt than do nontasters.Snack
foods have saltiness as their primary flavor,and at least for these foods,more is better,so the supertasters
seem to like them more."
However,supertasters also need higher levels of salt to block unpleasant bitter tastes in foods such as
cheese,Hayes noted."For example,cheese is a wonderful blend of dairy flavors from fermented milk,but
also bitter tastes from ripening that are blocked by salt,"he said."A supertaster finds low-salt cheese un-
pleasant because the bitterness is too pronounced．"
Hayes cited research done more than 75 years ago by a chemist named Fox and a geneticist named
Blakeslee,showing that individuals differ in their ability to taste certain chemicals.As a result,Hayes ex-
plained,we know that a wide range in taste acuity exists,and this variation is as normal as variations in eye
and hair color.
"Some people,called supertasters,describe bitter compounds as being extremely bitter,while others,
called nontasters,find these same bitter compounds to be tasteless or only weakly bitter."he said."Re-
sponse to bitter compounds is one of many ways to identify biological differences in food preference because
supertastmg is not limited to bitterness." The last two paragraphs illustrate that taste acuity is_________.
A.developed over time after birth
B.related to one's eye and hair color
C.still unknown to scientists
D.genetically determined