Young people think that living in the 21 st century ,they mu

Young people think that living in the 21 st century ,they must keep up with the time .They don’t want to fall(5) .Besides,they think that they need to keep in touch with their classmates,so they need mobile phones .They also like to (6) the pop music so they need CD players .They explain that ,just like electronic dictionaries ,these can be (7)for their study ,too They think that their parents should understand (8)they want these things.
（）5.A.down B.off C.behind
（）6.A.hear B.listen to C.make
（）7.A.useful B.modern C.latest
（）8.A.but B.which C.why