–What _______ if you don’t finish your work on time?

–Mrs Brown will be very angry.

A. happens           B. is happened     C. happened          D. will happen

Do you know why you sleep? You may think it’s because you’re tired. Or perhaps you’ve been told sleep is good for you. Yet no one knows exactly why or how people sleep.
Until the early 1950s, most scientists thought the body and brain rested during sleep. Then a scientist watched people sleep. He noticed that during periods of between 5 and 30 minutes each, sleepers’ eyes made rapid movements, as if they were watching something. He called these periods REM sleep, for Rapid Eye Movement. Periods when sleepers’ eyes did not move he called non-REM sleep.
Whenever the scientist woke people during REM sleep, they were having vivid dreams. Measurements showed that sleepers’ pulses（脉搏）went up quickly during REM sleep. Their breathing, heartbeat, and the blood going to the brain also increased. Far from being a time of rest, REM sleep is a time when the body is hard at work. Scientists still don’t know the reason for this. Some believe REM sleep makes learning easier. Babies spend a lot of time in REM sleep. Because of this, some scientists believe that REM sleep helps the brain grow. Others think REM sleep is a time for the brain to empty the day’s garbage.
One thing all the scientists agree on is that sleep is necessary. Without enough sleep, people make mistakes. Most major car accidents happen during the early morning hours, when people are sleepiest.
【小题1】During REM sleep, a person’s breathing and heartbeat ________.

We all know the dangers of fires. It’s good and necessary for a family to learn how to prepare for a fire. Here are some suggestions.

Put a smoke alarm(火警) in the house. Smoke from a fire causes the alarm to go off. The alarm makes a loud sound. The sound tells everyone to leave the house at once.
Make escape(逃脱) plans. We should know all the ways out of the house. If there is a fire, everyone follows the plan to get out. Part of the plan is to check all the windows to make sure they can be opened easily.
Buy fire extinguishers(灭火器) in the house. Everyone in the family should know how to use them.
Practise for a fire. We do fire practice because we teach children about fire safety. Everyone in the family should know the following fire rules:
★    Don’t open a hot door! The fire can grow more quickly if you open the door.
★    Stay close to the floor! Smoke can be more dangerous than fire. The best air is near the floor because smoke rises.
★    What will you do if your hair or clothes start to burn? First, stop! Don’t run! The fire burns faster because of more air. Drop! Fall to the floor. Then roll! Turning over and over will make the fire go out. Put a blanket(毯子) around you to keep air away from the fire that may still be on you.
There are many possible causes for fires. A wise family is ready all the time. If there is a fire, don’t forget to call 119 for help.
【小题1】When a smoke alarm rings at home, it means _________.

Mosquitoes(蚊子)can be seen everywhere all over the world, especially in summer. And there are more than 2,500 kinds of them.

__43_likes the mosquito, but the mosquito may like you. She thinks your blood is delicious.

She? Yes, she. It’s true that the male(雄性)mosquito doesn’t bite(咬)and only the female mosquito bites because she 　44 blood(血液)to lay eggs. She is always 　45 things or people she wants to bite. If she likes what she finds, she will bite. But if she doesn’t like your blood, she 　46 to someone else for more delicious blood. Next time a mosquito bites you, just remember you’re different from others.

If the mosquito likes you, she will land on your body 　47 letting you know. She bites you 48 quickly and quietly that you may feel nothing. After she bites, you will have an itch(痒)on your body because she puts something from her mouth together with your blood. By the time the itch begins, she has 　49　 .

And then what happens? Well, after her delicious 　50　 ,it’s dark. The mosquito feels　 51 .

She just wants to find a place to have a good rest. There, on a leaf or a wall, she begins to lay eggs, 　52　 eggs.

( ) 43.A.Everyone　　　　　　　 B. No one　　　　　　 C. Someone

( ) 44.A.needs　　　　　　　　 B. need　　　　　　　 C. want

( ) 45.A.finding　　　　　　　　 B. wants　　　　　　　 C. looking for

( ) 46.A.will turn　　　　　　　 B. turns to　　　　　　 C. turn

( ) 47.A.with　　　　　　　　　 B. without　　　 　　　C. after

( ) 48.A.so　　　　　　　　　　 B. such　　　　　　　 C. very

( ) 49.A.flies away　　　　　　　 B. flew away　　　　　 C. flown away

( ) 50.A.breakfast　　　　　　　 B. dinner　　　　　　　 C. lunch

( ) 51.A.tiring　　　　　　　　 B. tired　　　　　　　　 C. relaxing

( ) 52.A.3 hundreds　　　　　　 B. hundred of　　　　　 C. hundreds of