e．Ba
kscompa
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dgover
me
tage
ciesusesecretcodesi
doi
gbusi
essespeciallywhe
i
formatio
isse
tbycomputer．Peoplehaveusedsecretcodesforthousa
dsofyears．36Codebreaki
g
everlags落
后farbehi
dcodemaki
g．Thescie
ceofcreati
ga
dreadi
gcodedmessagesiscalledcryptography．Therearethreemai
typesofcryptography．37Forexamplethefirstlettersof“My
elepha
teatstooma
yeels”Spelloutthehidde
message“Meetme．”__38__Youmightreprese
teachletterwitha
umberForexampleLet’s
umberthelettersofthealphabeti
orderfrom1to26．Ifwesubstitutea
umberforeachletterthemessage“Meetme”wouldread“135520135．”
Acodeusessymbolstoreplacewordsphrasesorse
te
ces．
Toreadthemessageofareal
codeyoumusthaveacodebook．
39Forexample“bridge”mightsta
dfor“meet”a
d“out”40
mightsta
dfor“me．”Themessage“bridgeout”wouldactuallymea
“Meetme．”
Howeveritisalsohardtokeepacodebooksecretforlo
g．Socodesmustbecha
gedfreque
tly．
A．Itisveryhardtobreakacodewithoutthecodebook．B．I
a
yla
guagesomelettersareusedmoretha
others．
C．O
lypeoplewhok
owthekeywordca
readthemessage．D．Aslo
gastherehavebee
codespeoplehavetriedtobreakthem．E．Youca
hideamessagebyhavi
gthefirstlettersofeachwordspellitout．F．Withacodebookyoumightwritedow
wordsthatwouldsta
dforotherwords．G．A
otherwaytohideamessageistousesymbolstosta
dforspecificlettersofthealphabet．
f7．（2016新课标全国Ⅱ）
Agarde
that’sjustrightforyou
Haveyouevervisitedagarde
thatseemedjustrightforyouwheretheatmosphereofthegarde
appearedtototalmoretha
thesum总和ofitsparts36Butitdoes
’thappe

byaccide
tItstartswithlooki
gi
sideyourselfa
du
dersta
di
gwhoyouarewithrespecttothe
aturalworlda
dhowyouapproachthegarde
i
gprocess●37
Somepeoplemaythi
kthatagarde
is
omoretha
pla
tsflowerspatter
sa
dmassesofcolorOthersareco
cer
edaboutusi
ggarde
i
gmethodsthatrequirelesswatera
dfewerfertilizers肥料38Howevertherearea
umberofotherreaso
sthatmightexplai
why
youwa
ttogarde
O
eofthemcomesfromourearliestyears●Recall回忆yourchildhoodmemoriesOurmodelofwhatagarde
shouldbeofte
goesbacktochildhoodGra
dma’srosegarde
a
dDad’svegetablegarde
mightbegoodorbadbutthat’s
otwhat’simporta
t39
howbei
gi
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smadeusfeelIfyou’dliketobuildapowerfulbo
dwithyourgarde
startbytaki
gsometimetorecallthegarde
sofyouryouth40the
gooutside
a
dworkoutapla
totra
slateyourchildhoodmemoriesi
toyourgrow
upgarde
Havefu
A．K
owwhyyougarde
B．Fi
dagoodr