American researchers have developed a technique that may become an important tool in fighting AIDS virus from attacking its target-cells in the body's defense system．When AIDS virus enters the blood, it searches for blood cells called T4 lymphocytes(淋巴细胞)．The virus connects to the outside of T4 lymphocytes．Then it forces its way inside．There it directs the cells' genetic material to produce copies of the AIDS virus．This is how AIDS spreads．
Researchers think they may be able to stop AIDS from connecting to T4 cells．When AIDS virus finds a T4 cell, it actually connects to a part of the cell called CD4 protein．
Researchers want to fool the virus by putting copies or clones of the CD4 protein into the blood．This way the AIDS virus will connect to cloned protein instead of the real ones．Scientists use genetic engineering methods to make the clones．Normally a CD4 protein remains on the T4 cell at all times; the AIDS virus must go to it．
In a new technique, however, the cloned CD4 protein is not connected to a cell．It floats freely, so a lot more can be put into the blood to keep the AIDS virus away from real CD4 protein on T4 cells．One report says the AIDS virus connects to cloned protein just as effectively as it connects to real protein．That report was based on tests with blood cells grown in labs．The technique is just now beginning to be tested in animals．If successful, it may be tested in humans within a year．
(1)
The new technique can ________．
[ ]
A．
cure AIDS
B．
kill the AIDS virus
C．
prevent the AIDS virus from spreading
D．
produce new anti-AIDS cells
(2)
When the AIDS virus enters the blood, it is reproduced by ________．
[ ]
A．
itself
B．
the blood cells
C．
the CD4 protein
D．
the genetic material of T4 lymphocytes
(3)
The AIDS virus connects to cloned protein instead of the real CD4 protein because ________．
[ ]
A．
cloned protein stays on the T4 cells
B．
cloned protein floats freely, and many more can be put into the blood
C．
it connects to cloned protein more effectively
D．
cloned protein is made by genetic engineering methods
Below is a page adapted from an English dictionary．
stick
verb(stuck, stuck)
push sth in
[＋adv．/prep．] to push sth, usually a sharp object, into sth; to be pushed into sth：[VN] The nurse stuck the needle into my arm．◆ Don't stick your fingers through the bars of the cage．◆ [V] I found a nail sticking in the tyre．
attach
[＋adv．/prep．] to fix sth to sth else, usually with a sticky substance; to become fixed to sth in this way：[VN] He stuck a stamp on the envelope．◆ We used glue to stick the broken pieces together．◆ I stuck the photos into an album．◆ [V] Her wet clothes were sticking to her body．◆ The glue's useless-the pieces just won't stick．
put
[VN ＋adv．/prep．](informal)to put sth in a place, especially quickly or carelessly：Stick your bags down there．◆ He stuck his hands in his pockets and strolled off．◆ Can you stick this on the noticeboard? ◆ Peter stuck his head around the door and said, 'Coffee, anyone?' ◆(spoken)Stick 'em up!(＝put your hands above your head-I have a gun)
become fixed
[V]～(in sth)to become fixed in one position and impossible to move：The key has stuck in the lock．◆ This drawer keeps sticking．
difficult situation
(BrE, informal)(usually used in negative sentences and questions)to accept a difficult or unpleasant situation or person：[VN] I don't know how you stick that job．◆ They're always arguing-I can't stick it any longer．◆ The problem is, my mother can't stick my boyfriend．◆ [V -ing] John can't stick living with his parents．
become accepted
[V] to become accepted：The police couldn't make the charges stick(＝show them to be true)．◆ His friends called him Bart and the name has stuck(＝has become the name that everyone calls him)．
[V] to not take any more cards
Idioms：stick in your mind(of a memory, an image, etc．)to be remembered for a long time：One of his paintings in particular sticks in my mind．
stick in your throat/craw(informal)
(of words)to be difficult or impossible to say：She wanted to say how sorry she was but the words seemed to stick in her throat．
(of a situation)to be difficult or impossible to accept; to make you angry
stick your neck out(informal)to do or say sth when there is a risk that you may be wrong：I'll stick my neck out and say that Bill is definitely the best candidate for the job．
stick to your guns(informal)to refuse to change your mind about sth even when other people are trying to persuade you that you are wrong
Phrasal Verbs：stick around(informal)to stay in a place, waiting for sth to happen or for sb to arrive：Stick around; we'll need you to help us later．
stick at sth to work in a serious and determined way to achieve sth：If you want to play an instrument well, you've got to stick at it．
stick by sb [no passive] to be loyal to a person and support them, especially in a difficult situation：Her husband was charged with fraud but she stuck by him．
stick by sth [no passive] to do what you promised or planned to do：They stuck by their decision．
stick sth＜－＞down(informal)to write sth somewhere：I think I'll stick my name down on the list．
stick out to be noticeable or easily seen：They wrote the notice in big red letters so that it would stick out．
stick sth＜－＞out(of sth)to be further out than sth else or come through a hole; to push sth further out than sth else or through a hole：His ears stick out．◆ She stuck her tongue out at me．◆ Don't stick your arm out of the car window．
stick to sth
to continue doing sth in spite of difficulties：She finds it impossible to stick to a diet．
to continue doing or using sth and not want to change it：He promised to help us and he stuck to his word(＝he did as he had promised)．◆ 'Shall we meet on Friday this week?' 'No, let's stick to Saturday．' ◆ She stuck to her story．
stick together(informal)(of people)to stay together and support each other：We were the only British people in the town so we tended to stick together．
stick up to point upwards or be above a surface：The branch was sticking up out of the water．
stick with sb/sth [no passive](informal)
to stay close to sb so that they can help you：Stick with me and I'll make you a millionaire!
to continue with sth or continue doing sth：They decided to stick with their original plan．
noun
from tree
[C] a thin piece of wood that has fallen or been broken from a tree：We collected dry sticks to start a fire．◆ The boys were throwing sticks and stones at the dog．◆ Her arms and legs were like sticks(＝very thin)．
for walking
[C](especially BrE)＝WALKING STICK：The old lady leant on her stick as she talked．
in sport
[C] a long thin object that is used in some sports to hit or control the ball：a hockey stick
long thin piece
[C](often in compounds)a long thin piece of sth：a stick of dynamite ◆ carrot sticks ◆(AmE)a stick of butter
[C](often in compounds)a thin piece of wood or plastic that you use for a particular purpose：pieces of pineapple on sticks ◆ The men were carrying spades and measuring sticks．
in plane/vehicle
[C](informal, especially AmE)the control stick of a plane
[C](informal, especially AmE)a handle used to change the GEARS of a vehicle
for orchestra
[C] a BATON, used by the person who CONDUCTS an orchestra
criticism
[U](BrE, informal)criticism or harsh words：The referee got a lot of stick from the home fans．
country areas
(the sticks)[pl．](informal)country areas, a long way from cities：We live out in the sticks．
person
[C](old-fashioned, BrE, informal)a person：He's not such a bad old stick．
(1)
When Jimmy says：“Every morning, I have to take the crowded bus to school, which I really can't stick．”, he may feel _________．
[ ]
A．
worried
B．
curious
C．
annoyed
D．
discouraged
(2)
Due to her fashionable dress, the woman stuck out when she was walking in the street．“stuck out” in this sentence means “_________”．
[ ]
A．
be noticeable
B．
be followed
C．
be admired
D．
be envied
(3)
When I was in trouble, Paul was the only one who _________ to help me．
[ ]
A．
stuck in his throat
B．
stuck together
C．
stuck up
D．
stuck his neck out
(4)
Sally said to me：“Try a peaceful life out in the sticks, and you will experience something totally different．” She means _________．
[ ]
A．
I should go to the woods to enjoy a new life．
B．
I should ignore the criticism and enjoy myself．
C．
I should go to the remote areas to have a change．
D．
I should go out by plane instead of by train to change my feelings．
verb(stuck, stuck)
[＋adv．/prep．] to push sth, usually a sharp object, into sth; to be pushed into sth：[VN] The nurse stuck the needle into my arm．◆ Don't stick your fingers through the bars of the cage．◆ [V] I found a nail sticking in the tyre．
[＋adv．/prep．] to fix sth to sth else, usually with a sticky substance; to become fixed to sth in this way：[VN] He stuck a stamp on the envelope．◆ We used glue to stick the broken pieces together．◆ I stuck the photos into an album．◆ [V] Her wet clothes were sticking to her body．◆ The glue's useless-the pieces just won't stick．
[VN ＋adv．/prep．](informal)to put sth in a place, especially quickly or carelessly：Stick your bags down there．◆ He stuck his hands in his pockets and strolled off．◆ Can you stick this on the noticeboard? ◆ Peter stuck his head around the door and said, 'Coffee, anyone?' ◆(spoken)Stick 'em up!(＝put your hands above your head-I have a gun)
[V]～(in sth)to become fixed in one position and impossible to move：The key has stuck in the lock．◆ This drawer keeps sticking．
(BrE, informal)(usually used in negative sentences and questions)to accept a difficult or unpleasant situation or person：[VN] I don't know how you stick that job．◆ They're always arguing-I can't stick it any longer．◆ The problem is, my mother can't stick my boyfriend．◆ [V -ing] John can't stick living with his parents．
[V] to become accepted：The police couldn't make the charges stick(＝show them to be true)．◆ His friends called him Bart and the name has stuck(＝has become the name that everyone calls him)．
[V] to not take any more cards
[C](informal, especially AmE)a handle used to change the GEARS of a vehicle
[C] a BATON, used by the person who CONDUCTS an orchestra
[U](BrE, informal)criticism or harsh words：The referee got a lot of stick from the home fans．
(the sticks)[pl．](informal)country areas, a long way from cities：We live out in the sticks．
[C](old-fashioned, BrE, informal)a person：He's not such a bad old stick．