Ann is my best friend. She can play piano very well.( )
/
a
the
New energy cars have been ______ to cut down air pollution.( )
discovered
found
invented
refused
He tried many ways to solve the problem.But ______ of them worked.( )
neither
none
all
both
We are going to have a party ______ the evening of June 30th.( )
on
in
at
for
I'm sorry I took your card by mistake,but where is ______?( )
hers
theirs
yours
mine
Though Bill is very young,he has a lot of ______ about Chinese history.( )
information
knowledge
background
experience