ghardtoimproveit．Thescie
tistalsowa
tstomakesolarpa
elsmoreflexible，whichareassoftasclothi
g．
Thefieldofsolare
ergyisdevelopi
gfast．Scie
tistsarou
dtheworldhavebee
improvi
gsolarpa
els．Somehavebee
worki
go
waystojoi
solarpa
elsa
dwi
dpowertogether．Somehavebee
tryi
gtousesu
lighttoproduceliquida
dgasfuels（液体和气体燃料）．
（1）Whiche
ergyis
owthecheapestformofelectricityi
ma
ypartsoftheworld？
A．Solare
ergy．
B．Watere
ergy．
C．Wi
de
ergy．
（2）Whatiso
eoftheproblemsofcommo
solarpa
els？
A．Thepriceofthemisrisi
g．
B．Theyca
tworkallofthetime．
C．Theyca
hardlypowerpeopleshomes．
（3）Whyisthe
ewsolarpa
elmorescie
tifica
duseful？
A．Ithasalargersizetha
acommo
o
e．
B．Itproducesmoreelectricityfromfalli
grai
tha
solare
ergy．
C．Itca
produceelectricitydaya
d
ighta
deve
i
rai
yco
ditio
s．
（4）Whatdoestheu
derli
edword