单选题We can NOT conclude that the accelerometers ______.A are bound into three pairsB are able to sense fantastically small disturbancesC keep the satellite stable and prevent it from falling out of the skyD contain some very fragile mechanisms

共用题干
Tiny Invaders

The human body is truly amazing. It allows us to sense the world around us,to do work and have fun,
and to move from place to place.In fact,the human body does its work so well that most people don't think
about it very much一until they get sick.
The germs（致病菌）that make people sick are everywhere. You can ' t see them , but they ' re there.
They're sitting on your desk.They're hiding on your computer's keyboard.They're even in the air that you
are breathing. There are two types of germs : viruses and bacteria（细菌）.Viruses are germs that can only
live inside animals or plants. Viruses cause illnesses such as flu and measles（麻疹）.Bacteria are tiny
creatures.Some bacteria are good.They can help your stomach break down food.Other bacteria aren't so
good. They can make you sick. Bacteria can cause sore throats（喉痛）and ear infections.
How can you stop these tiny invaders from making you sick?Your skin is the first defense against
germs.You can prevent some illnesses simply by washing,with soap and water. But germs can still enter the
body through small cuts in the skin or through the mouth,eyes,and nose.
Once germs are inside your body, your immune（免疫的）system tries to protect you. It looks for and
destroys germs.How does it do that?Special cells patrol your body.Some of these cells actually eat germs!
Other cells make antibodies.An antibody sticks to a germ.There is a different antibody for each kind of
germ. Some antibodies keep germs from making you sick.Others help your body find and kill germs.After a
germ is destroyed,the antibodies stay in your body.They protect you if the same kind of germ comes back.
That way you will not get the same illness twice.
You can keep your body healthy by eating a nutritious（有营养的）diet to make your immune system
strong. You can also help your immune system fight germs by getting vaccinated（接种）.Vaccines are
medicines.They contain germs that have been killed or weakened.The dead germs can't make you sick.
Instead,they cause your body to make antibodies.If the same germ ever shows up again,then your
antibodies attack it.

Washing your skin can prevent some illnesses.
A:Right
B:Wrong
C:Not mentioned

From the article we can conclude that deadly night-shade is probably a kind of plant that is_______.

A.colorful
B.poisonous
C.ugly
D.Both A and B

共用题干
Hair Care
Whether the hair is long or short,it must be regularly brushed and regularly washed.For greasy（油性的）hair , especially if the owner lives in a town , it may be necessary to wash the head every four to five days.Those with a dry hair can usually go a little longer,but this is a matter for the individual to decide.
As for style,this must be studied according to what is the latest fashion and also to suit the individual at different times of her life.If a woman is not able to go to hairdresser very often,it is important that she chooses a style she can easily manage for herself,and this nearly always means that the first cut must be very standard. The same applies to permanent waving（烫发）.I think that this should be carried out three or four times a year,so that the hair never gets out of hand.
One thing would be remembered though,that is,whatever you apply to the head can have some effect upon the skin and therefore anything strong should be used with care.Or you may use milder products.
Young people who has spots or skin troubles on their face should take particular care to ensure that the hair is both clean and does not come into contact with the affected piece of skin.Hair is very difficult to keep completely clean and therefore anyone running their hands through their hair and afterwards touching their face,or letting their hair fall over their faces,might spread in- fection from one place to another.
Good hair does a lot to the effect of a face,so if you want to look charming,please start with your hair.

To prevent the hair from infecting the skin,we'd better______.
A: keep the hair completely clean
B: wash the hair very often
C: have hair cut four times a year
D: avoid combing the hair with our hands

共用题干
Some Things We Know About Language
Many things about language are a mystery,and many will always remain so.But some things we do know.
First , we know that all human beings have a language of some sort.There is no race（种族）of men anywhere on earth so backward that it has no language,no set of speech sounds by which the people communicate with one another.Furthermore,in historical times,there has never been a race of men without a language. Second,there is no such thing as a primitive（原始的）language.There are many people whose cultures are undeveloped,who are,as we say,uncivilized,but the languages they speak are not primitive.In all known languages we can see complexities that must have been tens of thousands of years in developing. This has not always been well understood;indeed,the direct contrary has often been stated.Popular ideas of the language of the American Indians will illustrate.Many people have supposed that the Indians communicated in a very primitive system of noises.Study has proved this to be nonsense.There are,or were, hundreds of American Indian languages,and all of them turn out to be very complicated and very old.They are certainly different from the languages that most of us are familiar with,but they are no more primitive than English and Greek.
A third thing we know about language is that all languages are perfectly adequate.That is,each one is a perfect means of expressing the culture of the people who speak the language. Finally,we know that language changes.It is natural and normal for language to change;the only languages which do not change are the dead ones.This is easy to understand if we look backward in time. Change goes on in all aspects of language.Grammatical features change as do speech sounds,and changes in vocabulary are sometimes very extensive and may occur very rapidly.Vocabulary is the least stable part of any language.

The author argues that we do know some things about language in______aspects.
A:three
B:four
C:five
D:six