Ancient poems，English words，historical events and so on，you must have a lot to remember at school.What if you could have a good memory？Scientists have done many experiments to find ways to help us have a good memory.Here is some advice based on their findings.
   Having intense（劇烈的） exercise
   Scientists asked people to either ride a bike slowly for 90 minutes or do it really fast for 6 minutes.It showed that the short but intense exercise made the brain produce more of a chemical which helps people remember things quickly.Its level goes to the highest point after six minutes of intense exercise.That's the time when you should be ready to remember things!
   Sleeping in a rocking bed
   When we were young，we slept well in our mother's swaying（搖晃的） arms.Scientists have found that if we sleep in a bed that gently sways back and forth，it is easier for us to fall asleep.Sleeping well improves our memories as well.So maybe，you could buy a rocking bed.
   Becoming emotional
   Besides sleep，emotions（情緒） can influence memories.The moment you become emotional，you can remember things really well.This is because the amygdala（杏仁核） in our brain is very useful for dealing with both emotions and memories.The brain wants us to remember what makes us so sad or happy.So next time you want to remember some knowledge，get yourself excited or angry.Then，just take out your book to learn new things!
   Practising by using it
   If you do not use your arms and legs for some time，they will become weak.When you start use them again，they slowly become strong again.Everybody knows that.Yet many people do not seem to know that memory works in the same way.When someone says that he has a good memory，he really means that he keeps his memory in practice by using it.
   When someone says his memory is poor，he really means that he does not give it enough chance to become strong.As a result，we need to use memory as often as possible.
根據(jù)短文內(nèi)容填空，每空不限一詞。
（1）Compared with long exercise，the

short but intense

short but intense

exercise makes the brain produce more of a chemical.And the chemical level will go the highest if we do intense exercise for

6 minutes/six minutes

6 minutes/six minutes

.
（2）We are advised to buy a

rocking bed

rocking bed

to sleep in.If it gently sways，we can fall asleep

more easily

more easily

.
（3）A good sleep can make our memories

better

better

.Besides，the amygdala in our brain is very useful for dealing with both emotions and memories.That is

why

why

emotions have an influence on memories.
（4）It is

necessary

necessary

for us to use memory as often as we can because our memory works in the same way as our

arms and legs

arms and legs

do—the more use，the better.
（5）According to the scientists' findings，in order to help us

have a good memory

have a good memory

，this passage offers us

4/four

4/four

pieces of advice.